Carbon and elastomer integration

ABSTRACT

Compounds having an elastomer material, a filler material, at least one additive material, and at least one accelerant material are disclosed. In various embodiments, the filler material comprises a graphene-based carbon material. In various embodiments, the graphene-based carbon material comprises graphene comprising up to 15 layers, carbon aggregates having a median size from 1 to 50 microns, a surface area of the carbon aggregates at least 50 m 2 /g, when measured via a Brunauer-Emmett-Teller (BET) method with nitrogen as the adsorbate, and no seed particles.

RELATED APPLICATIONS

This application is a continuation of U.S. patent application Ser. No.15/918,422 filed on Mar. 12, 2018, and entitled “Carbon and ElastomerIntegration; which claims the benefit of: 1) U.S. Provisional PatentApplication No. 62/472,058 filed on Mar. 16, 2017, and entitled “Carbonand Elastomer Integration”; 2) U.S. Provisional Patent Application No.62/581,533 filed on Nov. 3, 2017, and entitled “Carbon and ElastomerIntegration”; and 3) U.S. Provisional Patent Application No. 62/630,179filed on Feb. 13, 2018, and entitled “Carbon and Elastomer Integration”;all of which are hereby incorporated by reference for all purposes.

BACKGROUND

Rubber products, tires and seals are made by compounding or mixingfillers, such as carbon black and silica, into rubber, which is thenvulcanized. The rubber products typically contain 20-30% by weightcarbon black as a reinforcing filler, where the percentage and type ofcarbon black, the type of rubber used (e.g., natural, synthetic), andadditional additive materials and chemicals are varied to customize theproperties of the finished product. For vehicle tires, additionalstructural properties are introduced by embedding cords and by usingdifferent types of elastomer compounds in the tread, side wall andinterior lining. Carbon black—also known in the industry as, forexample, acetylene black and furnace black—is a type of amorphous carbonand is produced by combusting petroleum. A manufacturer, such as a tiremanufacturer, typically receives its raw materials (e.g., rubber, carbonblack, etc.) from different sources. Carbon black is a light andhard-to-handle material, which drives the tire industry to require thecarbon to be densified, i.e. pelletized, so that it can be handled moreeasily. Pelletizing also facilitates mixing of the carbon black whenadded to the elastomer compound. In order to pelletize the carbon,additives are usually required, which contaminate the carbon.

SUMMARY

In some embodiments, a compound comprises an elastomer material, afiller material, at least one additive material, and at least oneaccelerant material. The filler material comprises a graphene-basedcarbon material. The graphene-based carbon material comprises graphenecomprising up to 15 layers, carbon aggregates having a median size from1 to 50 microns, a surface area of the carbon aggregates of at least 50m²/g, when measured via a Brunauer-Emmett-Teller (BET) method withnitrogen as the adsorbate, and no seed particles.

In some embodiments, the graphene-based carbon material is a nano-mixedgraphene-based carbon material. In some embodiments, the graphene-basedcarbon material is a functionalized graphene-based carbon material.

In some embodiments, a G′ storage modulus at −20° C. of the compound, asmeasured by ASTM D5992-96 (2011), is less than 9 MPa; a tan delta at−10° C. of the compound, as measured by ASTM D5992-96 (2011), is greaterthan 0.8; a tan delta at 0° C. of the compound, as measured by ASTMD5992-96 (2011), is greater than 0.5; a tan delta at 30° C. of thecompound, as measured by ASTM D5992-96 (2011), is less than 0.25; a G′storage modulus at 30° C. of the compound, as measured by ASTM D5992-96(2011), is greater than 1.5 MPa; a J″ loss compliance at 30° C., asmeasured by ASTM D5992-96 (2011), is greater than 9E-8 1/Pa; a tan deltaat 60° C. of the compound, as measured by ASTM D5992-96 (2011), is lessthan 0.15; and/or a G′ storage modulus at 60° C. of the compound, asmeasured by ASTM D5992-96(2011), is greater than 1.5 MPa.

In some embodiments, a method of producing an elastomer compoundcomprises providing a reactor, providing a hydrocarbon process gas intothe reactor, performing hydrocarbon cracking of the hydrocarbon processgas in the reactor to produce a graphene-based carbon material, andmixing an elastomer material with at least one filler material, at leastone additive material, and at least one accelerant material. The fillermaterial comprises the graphene-based carbon material. Thegraphene-based carbon material comprises graphene having up to 15layers, carbon aggregates having a median size from 1 to 50 microns, asurface area of the carbon aggregates of at least 50 m²/g, when measuredvia a Brunauer-Emmett-Teller (BET) method with nitrogen as theadsorbate, and no seed particles.

In some embodiments of the methods, the reactor is a thermal reactor ora microwave reactor. In some embodiments, the graphene-based carbonmaterial is a functionalized graphene-based carbon material or anano-mixed graphene-based carbon material, and the hydrocarbon crackingin a reactor further comprises providing a second material into thereactor.

In some embodiments of the above methods, the hydrocarbon crackingprocess and the mixing an elastomer material with at least one fillermaterial, at least one additive material, and at least one accelerantprocess are performed at the same site.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1A shows a simplified schematic of a conventional carbon materialproduction chain.

FIG. 1B shows an example simplified schematic of a carbon materialproduction chain, in accordance with some embodiments.

FIG. 2 shows ASTM classifications of some carbon black materials fromthe prior art.

FIG. 3 shows a cross-section of a radial tire structure, with thecircled components indicating areas where the present graphene-basedcarbon integrated materials can be used, in accordance with someembodiments.

FIG. 4 shows analytical test results for graphene-based carbonmaterials, compared to conventional carbon black materials, inaccordance with some embodiments.

FIG. 5 shows a graph of oil absorption number versus iodine adsorptionnumber for graphene-based carbon materials compared to a range ofconventional carbon black materials, in accordance with someembodiments.

FIG. 6 shows a table of the formulations of an elastomer compoundcontaining graphene-based carbon materials compared to an elastomercompound containing conventional carbon black materials, in accordancewith some embodiments.

FIGS. 7 and 8 show physical properties of an elastomer compoundcontaining graphene-based carbon materials compared to an elastomercompound containing conventional carbon black materials, in accordancewith some embodiments.

FIG. 9 shows a table of the formulations of an elastomer compoundcontaining graphene-based carbon materials compared to an elastomercompound containing conventional carbon black materials, in accordancewith some embodiments.

FIG. 10 shows a table of some of the key parameters measured duringmixing of an elastomer compound containing graphene-based carbonmaterials compared to an elastomer compound containing conventionalcarbon black materials, in accordance with some embodiments.

FIG. 11 shows a table of physical properties of an elastomer compoundcontaining graphene-based carbon materials compared to an elastomercompound containing conventional carbon black materials, in accordancewith some embodiments.

FIG. 12 shows a table of physical properties after heat-aging of anelastomer compound containing graphene-based carbon materials comparedto an elastomer compound containing conventional carbon black materials,in accordance with some embodiments.

FIG. 13 shows a table of dynamic viscoelastic properties of an elastomercompound containing graphene-based carbon materials compared to anelastomer compound containing conventional carbon black materials, inaccordance with some embodiments.

FIG. 14 shows a table of dynamic viscoelastic properties of an elastomercompound containing graphene-based carbon materials normalized to anelastomer compound containing conventional carbon black materials, inaccordance with some embodiments.

FIG. 15 shows a radar chart of dynamic viscoelastic properties of anelastomer compound containing graphene-based carbon materials normalizedto an elastomer compound containing conventional carbon black materials,in accordance with some embodiments.

FIG. 16 shows a table of the formulations of elastomer compoundscontaining graphene-based carbon materials compared to an elastomercompound containing conventional carbon black materials, in accordancewith some embodiments.

FIG. 17 shows a table of the mixing parameters and observations from themixing for elastomer compounds containing graphene-based carbonmaterials compared to an elastomer compound containing conventionalcarbon black materials, in accordance with some embodiments.

FIG. 18 shows a table of some of the key parameters measured duringmixing of elastomer compounds containing graphene-based carbon materialscompared to an elastomer compound containing conventional carbon blackmaterials, in accordance with some embodiments.

FIG. 19 shows a table of physical properties of elastomer compoundscontaining graphene-based carbon materials compared to an elastomercompound containing conventional carbon black materials, in accordancewith some embodiments.

FIG. 20 shows a table of the formulations of an elastomer compoundcontaining graphene-based carbon materials compared to elastomercompounds containing conventional carbon black materials, in accordancewith some embodiments.

FIG. 21 shows a table of the mixing parameters and observations from themixing for an elastomer compound containing graphene-based carbonmaterials compared to an elastomer compound containing conventionalcarbon black materials, in accordance with some embodiments.

FIG. 22 shows a table of some of the key parameters measured duringmixing of an elastomer compound containing graphene-based carbonmaterials compared to elastomer compounds containing conventional carbonblack materials, in accordance with some embodiments.

FIG. 23 shows a graph of the torque during mixing of an elastomercompound containing graphene-based carbon materials compared toelastomer compounds containing conventional carbon black materials, inaccordance with some embodiments.

FIG. 24 shows a table of physical properties of an elastomer compoundcontaining graphene-based carbon materials compared to elastomercompounds containing conventional carbon black materials, in accordancewith some embodiments.

FIG. 25 shows a table of dynamic viscoelastic properties of an elastomercompound containing graphene-based carbon materials compared toelastomer compounds containing conventional carbon black materials, inaccordance with some embodiments.

FIG. 26 shows a table of dynamic viscoelastic properties of an elastomercompound containing graphene-based carbon materials and elastomercompounds containing conventional carbon black materials, normalized toan elastomer compound containing conventional carbon black materials, inaccordance with some embodiments.

FIG. 27 shows a radar chart of dynamic viscoelastic properties of anelastomer compound containing graphene-based carbon materials andelastomer compounds containing conventional carbon black materials,normalized to an elastomer compound containing conventional carbon blackmaterials, in accordance with some embodiments.

FIG. 28 shows a table of the formulations of elastomer compoundscontaining graphene-based carbon materials compared to an elastomercompound containing conventional carbon black materials, in accordancewith some embodiments.

FIG. 29 shows a table of some of the key parameters measured duringmixing of elastomer compounds containing graphene-based carbon materialscompared to an elastomer compound containing conventional carbon blackmaterials, in accordance with some embodiments.

FIG. 30 shows a graph of the torque during mixing of elastomer compoundscontaining graphene-based carbon materials compared to an elastomercompound containing conventional carbon black materials, in accordancewith some embodiments.

FIG. 31 shows a table of physical properties of elastomer compoundscontaining graphene-based carbon materials compared to an elastomercompound containing conventional carbon black materials, in accordancewith some embodiments.

FIG. 32 shows a table of physical properties after heat-aging ofelastomer compounds containing graphene-based carbon materials comparedto an elastomer compound containing conventional carbon black materials,in accordance with some embodiments.

FIG. 33 shows a table of dynamic viscoelastic properties of elastomercompounds containing graphene-based carbon materials compared to anelastomer compound containing conventional carbon black materials, inaccordance with some embodiments.

FIG. 34 shows a table of dynamic viscoelastic properties of elastomercompounds containing graphene-based carbon materials normalized to anelastomer compound containing conventional carbon black materials, inaccordance with some embodiments.

FIG. 35 shows a radar chart of dynamic viscoelastic properties ofelastomer compounds containing graphene-based carbon materialsnormalized to an elastomer compound containing conventional carbon blackmaterials, in accordance with some embodiments.

FIG. 36 shows a flowchart of an embodiment for producing an elastomercompound, in accordance with some embodiments.

DETAILED DESCRIPTION

Graphene-based carbon materials are described herein, which can be usedas reinforcing fillers for elastomer compounds. In some embodiments, thegraphene-based carbon materials include other materials, either byattaching the other materials species (e.g., atoms or compounds) to thesurfaces of the carbon materials, or by intimate mixing of the othermaterials with the carbon materials. The processing conditions of thegraphene-based carbon materials, and optionally the composition of theother materials included in the particles, can change the properties ofthe present carbon materials. The present carbon materials enable tuningof the properties of reinforced elastomers, since the properties of thepresent carbon materials can influence the processing and/or propertiesof elastomers containing these materials.

The ability to integrate rubber (both natural and synthetic rubber) withvarious materials (e.g., silica, carbon black, sulfur, etc.) inindustrial mixers of conventional mixing technology is limited. Thisconventional macro-mixing technology uses various chemicals to bindmaterials together, such as using silane to bind the silica/carbon tothe elastomer. Additionally, the transportation of carbon blackmaterials can be costly.

In contrast, the present materials and methods, in some embodiments,involve direct incorporation of graphene-based carbon materials into theproduction of elastomers, without needing the carbon materials to bealtered. For example, the present materials do not need to be pelletizedor compressed in order to densify the material for transportation,although they can be in some embodiments. The present graphene-basedcarbon materials have properties that enable them to be used assubstitutes for conventional carbon blacks in making elastomercompounds, such as rubber materials for dynamic and static systems. Insome embodiments, the graphene-based carbon materials are produced in areactor with or without the addition of various materials (e.g.,silicon, hydrogen gas, ammonia, hydrogen sulfide, metals, halogens), andintegrated into an elastomer formulation. In some embodiments, thegraphene-based carbon materials are produced by hydrocarbon cracking inthe reactor, where embodiments include thermal reactors and microwaveplasma reactors. Because these types of reactors are typicallyindividual units that are much smaller than a carbon black manufacturingplant, the embodiments enable on-site carbon material production. Thus,in some embodiments, the graphene-based carbon material is produced atthe same site where it is to be used, e.g., at an elastomer productionfacility.

On-site mixing alleviates the need for transporting the carbon rawmaterials to an elastomer production site, which consequently eliminatesthe need to pelletize the carbon for the said purpose of transportation.Since the carbon does not need to be pelletized, there is no need to useadditives to form the carbon pellets. As shall be described herein, thepresent materials can be tailored to provide desired physical propertiesof the finished elastomer. There are also environmental advantages ofnot pelletizing the carbon, such as reducing the amount of water andenergy required in the carbon production processes.

FIG. 1A shows a simplified schematic of a conventional carbon materialproduction chain, in comparison to FIG. 1B, which is an example of acarbon material production chain of the present embodiments. Inconventional technology, as illustrated in FIG. 1A, raw materials suchas carbon black 101, silica 102, and other chemicals 103 are transported110 to a manufacturing facility 120 where they are formulated into anelastomer compound and then processed into a finished product, such astires 130. A conventional tire supply includes the preparation of rawmaterials (e.g., rubber bales, carbon filler, textiles, steel and otheradditives), building the tire components (including extruding elastomercompounds for the tread and sidewalls), and then building the tire 130(including curing the tire, and inspecting the finished tire). In someembodiments of the present materials and methods as illustrated in FIG.1B, the carbon particle production, the mixing of the elastomercompounds, and optionally building the finished product (e.g.,automobile tires), can be done on-site. In some embodiments, nano-mixingof materials is also performed on-site. In the specific example shown inFIG. 1B, hydrocarbons 151 and silica 152 are mixed (i.e., integratedtogether) on-site in a reactor 160 at a manufacturing facility 170, thenintegrated with elastomer raw materials (e.g, rubber) to produce anelastomer compound, and then processed into a finished product such astires 180. The differentiation between FIGS. 1A and 1B exemplifies somepossible benefits of the present technology described above, such aseliminating the need for transporting the difficult to handle carbonblack materials and reducing energy consumption by integrating materialstogether during the carbon production process. In other embodiments, theconventional supply chain shown in FIG. 1A can be used in conjunctionwith the present graphene-based carbon materials. In such embodiments,the carbon materials are produced at one site, and then the carbonmaterials and other component materials are transported to amanufacturing facility where they are formulated into an elastomercompound and then processed into a finished product, such as tires.

Another benefit of using the present graphene-based carbon materials isthe improved purity compared to carbon black. In some cases, theimpurities in carbon black (e.g., residual oil) require the carbon to belabeled as carcinogenic. In some embodiments, the present graphene-basedcarbon materials have lower volatile organic compounds (VOCs) thancarbon black, and do not result in residual oil on the surface of theproduced elastomer material. In other cases, the present graphene-basedcarbon materials have a lower concentration of residual hydrocarbons(e.g., polycyclic aromatic hydrocarbons) compared to carbon black,resulting in less residual oil on the surface of the produced elastomermaterial. The carbon materials described herein also contain lowconcentrations of contaminants (e.g., ash, metals, and other elementalcontaminants) compared to conventionally processed carbon black orgraphene. Also, there are minimal CO₂, NO_(x), and SO_(x), emissions asproduction by-products. All these benefits result in the present carbonmaterials being safer to handle and more environmentally friendly thanthe conventional carbon black that is used for elastomers.

The reduced concentration of impurities of the present graphene-basedcarbon materials compared to carbon black is also a benefit forprocessing the carbon materials (e.g., carbon post-processes, andelastomer compounding). For example, conventional carbon blackprocessing equipment can require specialized systems to process thetoxic carbon black particles. In contrast, specialized systems are notneeded to process the present non-toxic or low toxicity materials. Insome cases, conventional carbon black will contaminate processingequipment, and therefore is unable to be processed by some facilities.In some embodiments, the present materials with lower concentrations ofimpurities would not be restricted from being processed byuncontaminated processing equipment.

Graphene-Based Carbon Materials

There are three properties that affect the ability of a particularcarbon material to reinforce elastomers: surface area, structure, andsurface activity. In addition, impurities, such as coke, ash andmoisture can be important to the effectiveness of a carbon materialfiller in an elastomer. Surface area refers to the total area of thecarbon material surface, including that which is available to interactwith the elastomer. Particle size and shape can affect the surface area.Smaller carbon particles (e.g., less than 100 nm in average diameter)typically fuse together to form larger aggregates (e.g., 1˜10 micronsaverage diameter). Structure describes the shape of the aggregate. Thestructure can be affected by the number of particles fused together andthe configuration of the particles within the aggregate. For example,aggregates with larger numbers of particles can have complex shapes withlarge void volumes created. The structure can affect the degree ofmixing of the carbon and the polymer (e.g., voids can be filled with thepolymer), which can affect the properties of the elastomer/carboncompound. Surface activity refers to the strength of the surfaceinteraction between the carbon filler material and the polymer. Surfaceactivity can impact the dispersion properties of the carbon materialswithin the elastomer. Compound mechanical properties such as tensilestrength, tear strength, and abrasion resistance can be affected bysurface area of the carbon filler material. Other compound mechanicalproperties such as viscosity, shrinkage, and modulus can be affected bythe structure of the carbon filler material. Surface area also canaffect some compound mechanical properties such as hysteresis. Structurecan also affect flex fatigue and abrasion resistance in reinforcedelastomeric compounds. Surface activity can affect compound mechanicalproperties as well, such as modulus, hysteresis, and abrasionresistance.

Several tests can be used to measure the surface area and the structureof carbon black. The most common measurements are iodine adsorption(e.g., using ASTM D1510) and oil absorption (e.g., using ASTM 2414,Method B). The resulting metrics are the iodine absorption number, whichis a measure of the surface area of the carbon material, and the dibutylphthalate absorption (DBP) number, which is a measure of the structureof the carbon material.

FIG. 2 shows ASTM classifications of some conventional carbon blackmaterials with properties that are in the range of some of thegraphene-based materials described herein. As described below (andthroughout this disclosure), the materials incorporated into, and theprocessing conditions of, the present graphene-based carbon materialscan be changed to tune the physical properties of the particlesproduced. In some embodiments, the graphene-based materials describedherein have an iodine adsorption number from 20 to 160, and oilabsorption numbers from 50 to 180. For example, a graphene-basedmaterial described herein has an iodine adsorption number of 110 and anoil absorption number of 92, which is a similar surface area andstructure as conventional N125, N219 and N299 (values listed in FIG. 2).For another example, a graphene-based material described herein has aniodine adsorption number of 46 and an oil absorption number of 75, whichis a similar surface area and structure as conventional N660, N762, N772and N774 (FIG. 2). These results suggest that the graphene-based carbonmaterials described herein can be suitable replacements for severalgrades of conventional carbon black.

There are a number of methods and materials that can be used to tune thesurface area, structure, and surface activity of the carbon materialsdescribed herein (e.g., the graphene-based carbon materials).

In some embodiments, the surface area, structure, and surface activityof the carbon materials described herein are tuned by functionalizingthe carbon materials. Functionalization of the carbon materials refersto adding elements, functional groups, or molecules to the carbonmaterials. In some embodiments, the elements, functional groups, ormolecules are covalently bonded to the carbon atoms in the carbonmaterial. In some embodiments, the elements, functional groups, ormolecules are physically adsorbed into the carbon porosity of the carbonparticles and/or aggregates. The functionalization reactions can occurin situ (i.e., as the carbon materials are being produced viahydrocarbon cracking in the reactor), or can occur in one or morepost-processing steps, or can occur in a combination of in situ andpost-processing steps. Elastomeric compounds that incorporatefunctionalized carbon materials described herein can benefit from afaster rate of cure, improved elastic moduli, improved abrasionresistance and improved electrical conductivity.

In some embodiments, the surface area, structure, and surface activityof the carbon materials described herein are tuned by nano-mixing thecarbon particles within the carbon materials with particles of othermaterials. In some embodiments, particles of nano-mix additive materialscan be beneficially integrated with the particles of the graphene-basedcarbon on a particle level, which shall be referred to as nano-mixing inthis disclosure. The average diameter of the particles of the nano-mixadditive material and the graphene-based carbon materials in thenano-mixture can be from 1 nm to 1 micron, or from 1 nm to 500 nm, orfrom 1 nm to 100 nm, or can be as small as 0.1 nm. In some embodiments,the nano-mix additive material and the graphene-based carbon materialare chemically bound, or are physically bound, together in thenano-mixture. The nano-mixing involves introducing nano-mix additivesduring the hydrocarbon cracking process such that the nano-mix additivematerial is integrated into the graphene-based carbon material as thecarbon material is produced, rather than combining a carbon raw materialwith an additive in a later process as in conventional methods (e.g.,the macro-mixing mentioned above). For example, the resulting nano-mixedcarbon materials of the present embodiments can contain particles ofsilica, ZnO, and/or metals. The nano-mix additive material can beintroduced into the reactor as a gas, liquid, or colloidal dispersion.As an example, silica or silicon can be input into the reactor alongwith a hydrocarbon process gas (or other carbon-containing processmaterial such as a liquid alcohol) to produce silica in combination withcarbon materials and/or silicon wrapped in or coated with graphene,graphene-based carbon materials, and/or other carbon allotropes.

In some embodiments, an elastomer compound comprises an elastomermaterial and a filler material, the filler material containing agraphene-based carbon material, and silica. In some embodiments, themajority of the filler material is either graphene-based carbon materialor silica. In some embodiments, the ratio of silica to thegraphene-based carbon material in the elastomer compound is from 10:1 to1:1, or from 20:1 to 1:1, or from 100:1 to 1:1. Examples of nano-mixedmaterials in such embodiments include solid inorganic materials coatedin organic materials (e.g., silicon coated with graphene), and compositematerials with interlayers of organic/inorganic materials (e.g., asilica or silicon core with a layer of carbon encapsulating the silicon,coated with an additional inorganic layer). By introducing the nano-mixadditives during the hydrocarbon cracking process, the materials areintegrated at a nano-scale, rather than needing coupling agents to bondsilica and carbon together. The present nano-mixed carbon materialsenable reduced energy consumption for production of rubber or otherelastomers. Less energy is needed for mixing materials, since somematerials are integrated together. In some embodiments, the carbonparticles and the nano-mix additive particles in a nano-mixed carbonmaterial have average diameters of less than 1 micron, or less than 100nm, or less than 10 nm. Elastomeric compounds that incorporatenano-mixed carbon materials described herein can benefit from a fasterrate of cure, improved elastic moduli, improved abrasion resistance andimproved electrical conductivity.

In some embodiments, particulate, liquid and/or gaseous materials can beinput into the reactor along with a hydrocarbon process gas (or othercarbon-containing process material such as a liquid alcohol) to producecarbon materials that are nano-mixed with other materials and/orfunctionalized carbon materials. The produced mixed carbon and/orfunctionalized carbon materials can contain graphene-based carbonmaterials and/or other carbon allotropes, in different embodiments.

For example, by incorporating and/or by adding liquids or gasescontaining S, liquids or gases containing Si, hydrogen, hydrogensulfide, silane gas, and/or ammonia gas or liquid into the reactor alongwith a hydrocarbon process gas, the reactor system can producefunctionalized carbon materials with H, S, Si and/or N incorporated intothe carbon materials. Elastomeric compounds that incorporate thefunctionalized carbon materials described herein (e.g., with improvedstructures, and including H, S and/or N) can benefit from a faster rateof cure, improved elastic moduli, improved abrasion resistance andimproved electrical conductivity. The incorporation of liquids or gasescontaining S, liquids or gases containing Si, H₂ gas, H₂S gas, silanegas, and/or ammonia gas or liquid during the hydrocarbon cracking carbonparticle formation process can create carbon particles with improvedsurface area, structure, and/or surface activity.

In another example, adding aromatic compounds into the reactor alongwith a hydrocarbon process gas can produce functionalized carbonmaterials with the aromatic compounds incorporated into the carbonmaterials. Some examples of aromatic compounds are compounds includingbenzene rings, pyridine rings, furan rings, thiophene rings, and/orpyrrole rings, such as benzene and derivatives of benzene, naphthalene,and azulene. In some embodiments, the aromatic compounds can break down,decompose, and/or crack or partially crack during the hydrocarboncracking carbon particle formation process, forming reaction products.In some cases, these reaction products can functionalize, or nano-mixwith the carbon materials being formed. For example, the aromaticcompounds can form other hydrocarbons with high boiling points, andthese high boiling point hydrocarbons can condense on the particlesurfaces, affecting the surface activity. In another example, thesereaction products can become bound to the carbon surfaces while theparticles and aggregates are being formed, which can affect the surfacearea, structure and the surface activity of the resulting functionalizedcarbon materials. The incorporation of aromatic compounds during thehydrocarbon cracking carbon particle formation process can create carbonparticles with improved surface area, structures and/or surfaceactivity.

In another example, adding one or more oils into the reactor along witha hydrocarbon process gas can produce functionalized carbon materialswith the oil incorporated into the carbon materials. Similar to theexample in the preceding paragraph, the oil can partially or fully crackand the products can be incorporated in and/or can condense on thesurface of the produced carbon materials.

In another example, adding metals, such as particles, gases or liquidscontaining S, Si, Na, K, B, Cr, Ca, Sr, Mg, Zn, Ga, Rb, Cs, B, Mn,alkali metals and other metals, into the reactor along with ahydrocarbon process gas can produce functionalized and/or nano-mixedcarbon materials with the metals incorporated into the carbon materials.The incorporation of metals during the hydrocarbon cracking carbonparticle formation process can create carbon particles with improvedsurface area, structures and/or surface activity. In some embodiments,alkali metals can be incorporated into the functionalized graphene-basedcarbon materials and the alkali metals functions as a coupling agent toimprove the adhesion between the carbon materials and the elastomermaterials in a compound.

In another example, adding halogens, such as particles, gases or liquidscontaining F, Cl, Br, I, and other halogens, into the reactor along witha hydrocarbon process gas can produce functionalized carbon materialswith the halogens incorporated into the carbon materials. Theincorporation of halogens during the hydrocarbon cracking carbonparticle formation process can create carbon particles with improvedsurface area, structures and/or surface activity.

In another example, adding particles, such as oxides (e.g., silica, zincoxide, titanium dioxide) or metals, into the reactor along with ahydrocarbon process gas can produce nano-mixed carbon materials with theparticles of the nano-mix additive and the particles of the carbonmaterials forming aggregates together. The incorporation of nano-mixadditive particles during the hydrocarbon cracking carbon particleformation process can create nano-mixed carbon particles with improvedsurface area, structures and/or surface activity.

In another example, adding oxygen-containing reactants or oxidizingreactants into the reactor along with a hydrocarbon process gas canproduce functionalized carbon materials with oxygen incorporated intothe carbon materials. Some examples of oxygen-containing or oxidizingreactants are ozone, hydrogen peroxide, potassium hydroxide, potassiumchloride, hydrochloric acid, nitric acid, chromic acid, permanganatesand diazonium salts. The oxygen-containing or oxidizing materials can beadded to the reactor in concentrations of the reactive species in theoxygen-containing or oxidizing materials (e.g., O, K, Cl, etc.) to thecarbon in the hydrocarbon process gas from 5 ppm to 100 ppm, or 5 ppm to30 ppm, or greater than 5 ppm, or greater than 15 ppm. The incorporationof oxygen-containing reactants or oxidizing reactants during thehydrocarbon cracking carbon particle formation process can create carbonparticles with improved surface area, structures and/or surfaceactivity. Oxidized carbon materials tend to slow the cure time of areinforced elastomer. Therefore, incorporating oxidized carbon materialsinto a reinforced elastomer compound can enable the tuning of the curetime, which can improve the resulting mechanical properties of the curedcompound.

In some embodiments, the carbon materials described herein (e.g.,graphene-based carbon materials) contain engineered surfaces, such aspreferentially exposed crystal planes, graphitic edges, and/orcrystallite edges. In some embodiments, these engineered surfaces arethe result of the particle synthesis conditions within the reactor,additives into the reactor that functionalize and/or nano-mix with theparticles during formation, or post-processing.

In some embodiments, the carbon materials used in the filler materialare described in U.S. patent application Ser. No. 15/711,620, entitled“Seedless Particles with Carbon Allotropes,” which is assigned to thesame assignee as the present application, and is incorporated herein byreference as if fully set forth herein for all purposes. In someembodiments, the compounds contain graphene-based carbon materials thatcomprise a plurality of carbon aggregates, each carbon aggregate havinga plurality of carbon nanoparticles, each carbon nanoparticle includinggraphene, with no seed (i.e., nucleation or core) particles. Thegraphene in the graphene-based carbon material has up to 15 layers. Apercentage of carbon to other elements, except hydrogen, in the carbonaggregates is greater than 99%. A median size of the carbon aggregatesis from 1 to 50 microns. A surface area of the carbon aggregates is atleast 50 m²/g, when measured using a Brunauer-Emmett-Teller (BET) methodwith nitrogen as the adsorbate. The carbon aggregates, when compressed,have an electrical conductivity greater than 500 S/m, such as up to20,000 S/m, or up to 90,000 S/m.

In some embodiments, compounds contain graphene-based carbon materialsthat comprise a plurality of carbon aggregates, each carbon aggregatehaving a plurality of carbon nanoparticles, each carbon nanoparticleincluding graphene and multi-walled spherical fullerenes, with no seedparticles. The graphene in the graphene-based carbon material has up to15 layers. A Raman spectrum of the graphene-based carbon materialcomprising the multi-walled spherical fullerenes, using 532 nm incidentlight, has: a D-mode peak, a G-mode peak, and a D/G intensity ratio lessthan 1.2. A percentage of carbon to other elements, except hydrogen, inthe carbon aggregates is greater than 99%. A median size of the carbonaggregates is from 1 to 100 microns. A surface area of the carbonaggregates is at least 10 m²/g, when measured using a BET method withnitrogen as the adsorbate. The carbon aggregates, when compressed, havean electrical conductivity greater than 500 S/m, such as up to 20,000S/m, or up to 90,000 S/m.

In some embodiments, compounds contain graphene-based carbon materialsthat comprise a plurality of carbon aggregates, each carbon aggregatehaving a plurality of carbon nanoparticles, each carbon nanoparticleincluding a mixture of graphene and at least one other carbon allotrope,with no seed (i.e., nucleation or core) particles. The graphene in thegraphene-based carbon material has up to 15 layers. A percentage ofcarbon to other elements, except hydrogen, in the carbon aggregates isgreater than 99%. A median size of the carbon aggregates is from 1 to100 microns. A surface area of the carbon aggregates is at least 10m²/g, when measured using a BET method with nitrogen as the adsorbate.The carbon aggregates, when compressed, have an electrical conductivitygreater than 100 S/m, or greater than 500 S/m, such as up to 20,000 S/m,or up to 90,000 S/m.

In some embodiments, the carbon materials used in the filler materialare produced using microwave plasma reactors and methods, such as anyappropriate microwave reactor and/or method described in U.S. Pat. No.9,812,295, entitled “Microwave Chemical Processing,” or in U.S. Pat. No.9,767,992, entitled “Microwave Chemical Processing Reactor,” which areassigned to the same assignee as the present application, and areincorporated herein by reference as if fully set forth herein for allpurposes.

In some embodiments, the carbon materials used in the filler materialare described in U.S. Pat. No. 9,862,606 entitled “Carbon Allotropes,”which is assigned to the same assignee as the present application, andis incorporated herein by reference as if fully set forth herein for allpurposes.

In some embodiments, the carbon materials used in the filler materialare produced using thermal cracking apparatuses and methods, such as anyappropriate thermal apparatus and/or method described in U.S. Pat. No.9,862,602, entitled “Cracking of a Process Gas,” which is assigned tothe same assignee as the present application, and is incorporated hereinby reference as if fully set forth herein for all purposes.

In some embodiments, the carbon material used in the filler has a ratioof carbon to other elements, except hydrogen, greater than 99%, orgreater than 99.5%, or greater than 99.7%, or greater than 99.9%, orgreater than 99.95%.

In some embodiments, the surface area of the carbon material used in thefiller, when measured using the Brunauer-Emmett-Teller (BET) method withnitrogen as the adsorbate (i.e., the “BET method using nitrogen”, or the“nitrogen BET method”) or the Density Functional Theory (DFT) method, isfrom 50 to 1500 m²/g, or from 50 to 1000 m²/g, or from 50 to 550 m²/g,or from 50 to 450 m²/g, or is from 50 to 300 m²/g, or from 100 to 300m²/g, or from 50 to 200 m²/g, or from 50 to 150 m²/g, or from 60 to 110m²/g, or from 50 to 100 m²/g, or from 70 to 100 m²/g.

In some embodiments, the carbon materials used in the filler, whencompressed (e.g., into a disk, pellet, etc.), and optionally annealed,have an electrical conductivity greater than 500 S/m, or greater than1000 S/m, or greater than 2000 S/m, or from 500 S/m to 20,000 S/m, orfrom 500 S/m to 10,000 S/m, or from 500 S/m to 5000 S/m, or from 500 S/mto 4000 S/m, or from 500 S/m to 3000 S/m, or from 2000 S/m to 5000 S/m,or from 2000 S/m to 4000 S/m, or from 1000 S/m to 5000 S/m, or from 1000S/m to 3000 S/m.

In some embodiments, the carbon materials used in the filler, whencompressed (e.g., into a disk, pellet, etc.), and optionally annealed,have thermal conductivity from 10 W/(m*K) to 5000 W/(m*K), or from 10W/(m*K) to 1500 W/(m*K), or from 10 W/(m*K) to 100 W/(m*K), or from 1W/(m*K) to 1000 W/(m*K).

The surface area, structure and/or surface activity of the carbonmaterials described herein (e.g., graphene-based carbon materials withor without functionalization and/or nano-mixing) can be tuned bychanging the parameters during the carbon particle production. Forexample, the input materials (i.e., reactants) to the reactor can affectthe surface area, structure and/or surface activity of the producedcarbon materials. Some examples of input materials are gaseoushydrocarbons such as methane, and liquid alcohols such as isopropylalcohol. In another example, the residence time within the reactor canaffect the allotropes of carbon formed as well as the size of theparticles and the size and the shape (i.e., structure) of the aggregatesformed. In some embodiments, the residence time is affected by the flowrate of the input materials into the reactor. Some other examples ofprocess parameters that can affect the surface area of the carbonmaterial are reaction temperature, gas velocity, and reactor pressure.Additionally, the flow dynamics (i.e., laminar flow or turbulent flow)within the reactor can affect the produced carbon materials structures.The patents and patent applications incorporated by reference aboveprovide examples of carbon materials (e.g., graphene-based carbonmaterials) with desirable surface areas and structures, and systems andmethods for producing the present graphene-based carbon materials.

Returning to FIG. 2, this figure shows a partial list of conventionalcarbon materials, and some properties characterizing these materialsaccording to ASTM standards. The properties of the graphene-based carbonmaterials described herein can be tuned such that they can be directreplacements for all grades of ASTM carbon classifications for tires,including but not limited to the grades shown in FIG. 2. Morespecifically, the graphene-based carbon materials (including thefunctionalized and the nano-mixed carbon materials) described herein canbe tuned such that they can be direct replacements for N339 through N110ASTM carbon classifications for tires. For example, in the case ofgraphene-based carbon materials produced using microwave reactors, themicrowave processing parameters can be changed to affect which carbonallotropes form, and the production rate of each, which will affect theproperties of the graphene-based carbon materials and the properties ofthe compounds incorporating those materials. Some non-limiting examplesof microwave processing parameters that can be changed to affect theproperties of the graphene-based carbon materials produced are precursormaterial flow rate, microwave parameters (e.g., energy, power, pulserate), chamber geometry, reaction temperature, the presence of afilament, and the precursor and supply gas species utilized. In additionto being direct replacements for carbon materials in tires, thegraphene-based carbon materials described herein can be directreplacements for carbon fillers in other elastomeric compounds as well.

In some embodiments, the species that are added into the reactor tofunctionalize or nano-mix with the carbon particles being produced areinput into the reactor in the zone where the carbon particles and/oraggregates are being formed, or are input into the reactor downstreamfrom the zone where the carbon particles and/or aggregates are beingformed. For example, a functionalizing gas, such as H₂S, can be inputinto the reactor zone where the carbon particles and/or aggregates arebeing formed, and the constituents of the functionalizing gas, such asS, are incorporated into the carbon particle as they are being formed.In that case, the functionalizing gas can affect the surface area,structure and surface activity of the carbon particles, by beingincorporated into each graphitic layer as the carbon particles areforming. In another example, a functionalizing gas, such as ozone, canbe input into the reactor zone downstream from where the carbonparticles and/or aggregates are being formed. In that case, thefunctionalizing gas can affect the surface area, structure and surfaceactivity of the carbon particles, by affecting the carbon particlesand/or agglomerates after they are formed. In the case of ozone, thiscan be accomplished by etching and/or pitting the surface of the formedcarbon particles and/or aggregates, thereby increasing their surfacearea.

In some embodiments, the carbon materials used in the filler materialare produced using reactors with multiple reactor chambers. In someembodiments, one or more of the reactor chambers is a thermal reactorchamber and one or more of the chambers is a microwave plasma reactorchamber. In different embodiments, the multiple reactor chambers can beconfigured in parallel with one another, in series with one another, orin a combination of parallel and series with one another. In someembodiments, one of the chambers is configured to form graphene-basedcarbon particles with particular properties, those particles aretransferred to a second chamber, and the second chamber is configured toform graphene-based carbon materials on and/or around the particles withdifferent properties. In other embodiments, a first chamber isconfigured to form graphene-based carbon particles with particularproperties, and a second chamber is configured to form graphene-basedcarbon particles with different properties, and the outlets of the twochambers are connected (e.g., in a “T” connection) such that the firstset of particles and the second set of particles are formed separatelyand then subsequently mixed together after formation.

In some embodiments, the carbon materials used in the filler materialare produced using reactors with multiple reactor chambers, and one ofthe chambers is used to process a nano-mix additive material (e.g., toform nano-mix additive particles from input process gases or liquids).The processed nano-mix additive material can then be transferred to asubsequent chamber where a process material (e.g., a hydrocarbon gas) iscracked to form nano-mixed graphene-based carbon materials.

In some embodiments, the carbon materials used in the filler materialare produced using reactors with multiple reactor chambers, and one ormore reactor chambers are used to functionalize the graphene-basedcarbon materials, the nano-mix additive materials, and/or the nano-mixgraphene-based carbon materials. For example, a reactor can containthree chambers. The first chamber in this example can form nano-mixmaterial particles (e.g., forming silica particles by cracking silanegas). The second chamber in this example can functionalize the nano-mixmaterial particles (e.g., by adding a coupling agent molecule onto thesilica particles). The third chamber in this example can formgraphene-based carbon nano-mixed with the functionalized silicaparticles (e.g., by cracking a hydrocarbon process gas). For anotherexample, a fourth chamber can be added to the three-chamber system inthe previous example, where the fourth chamber additionallyfunctionalizes the nano-mixed graphene-based carbon materials (e.g., byadding a second coupling agent molecule to the exposed graphene-basedcarbon surfaces of the nano-mixed particles).

The surface area, structure and surface activity of the carbon materialsand/or aggregates described herein can also be tuned usingpost-processing. In some embodiments, the functionalization or mixing ofthe carbon materials (e.g., graphene-based carbon materials) with otherspecies is done using post-processing, rather than processes within thereactor. In some embodiments, the carbon materials and/or aggregates(e.g., containing graphene) described herein are produced and collected,and no post-processing is done. In other embodiments, the carbonmaterials and/or aggregates described herein are produced and collected,and some post-processing is done. Some examples of post-processinginclude mechanical processing, such as ball milling, grinding, attritionmilling, micro-fluidizing, jet milling, and other techniques to reducethe particle size without damaging the carbon allotropes containedwithin. Some examples of post-processing include exfoliation processessuch as shear mixing, chemical etching, oxidizing (e.g., Hummer method),thermal annealing, doping by adding elements during annealing (e.g., S,and N), steaming, filtering, and lypolizing, among others. Some examplesof post-processing include sintering processes such as SPS (Spark PlasmaSintering, i.e., Direct Current Sintering), Microwave, and UV(Ultra-Violet), which can be conducted at high pressure and temperaturein an inert gas. In some embodiments, multiple post-processing methodscan be used together or in series. In some embodiments, thepost-processing will produce functionalized carbon nanoparticles oraggregates described herein.

In some embodiments, the surface area of the carbon aggregates afterpost-processing (e.g., by mechanical grinding, milling, or exfoliating),when measured using the nitrogen Brunauer-Emmett-Teller (BET) (i.e., theBET method with nitrogen as the adsorbate) or the Density FunctionalTheory (DFT) method, is from 50 to 1500 m²/g, or from 50 to 1000 m²/g,or from 50 to 550 m²/g, or from 50 to 450 m²/g, or from 50 to 300 m²/g,or from 100 to 300 m²/g, or from 50 to 200 m²/g, or from 50 to 150 m²/g,or from 60 to 110 m²/g, or from 50 to 100 m²/g, or from 70 to 100 m²/g.

In some embodiments, the carbon materials and/or aggregates describedherein are produced and collected, and subsequently additional elementsor compounds are added, thereby changing the surface area, structureand/or surface activity. For example, sulfur can be added in apost-process to increase the surface area of the carbon materials and/oraggregates by forcing the carbon layers to separate. For example, addingsulfur can increase the surface area by 2 or 3 times compared with thematerial without sulfur. Another method to increase the surface area isthrough oxidation post-processes. The methods described herein, e.g.,using sulfur, can produce particles with high surface areas that areconductive.

In some embodiments, the surface area of the carbon materials and/oraggregates after subsequent processing that adds additional elements(e.g., sulfur), when measured using the nitrogen Brunauer-Emmett-Teller(BET) or the Density Functional Theory (DFT) method, is from 50 to 1500m²/g, or from 50 to 1000 m²/g, or from 50 to 550 m²/g, or from 50 to 450m²/g, 50 to 300 m²/g, or from 100 to 300 m²/g, or from 50 to 200 m²/g,or from 50 to 150 m²/g, or from 60 to 110 m²/g, or from 50 to 100 m²/g,or from 70 to 100 m²/g.

Elastomers Containing Graphene-Based Carbon Materials

Although embodiments shall be described for applications in tiremanufacturing, the embodiments can be utilized in any manufacturingprocess relating to or associated with production of elastomercompounds. Embodiments include elastomer compounds that are made of anelastomer raw material (or an elastomer material) and a filler material,where the filler material includes carbon materials (e.g., thegraphene-based carbon materials, carbon black, etc.), silica, and otherreinforcing filler materials. In some embodiments, a graphene-basedcarbon material makes up a majority of the filler material. Someexamples of elastomeric materials are synthetic rubber, natural rubber,styrene-butadiene rubber (SBR), Standard Malaysia Rubber Grade L (SMRL),nitrile rubber, silicone rubber, and fluoroelastomers. Thegraphene-based carbon material comprises graphene, such as at least 5%graphene, or at least 10% graphene. In some embodiments, thegraphene-based carbon material contains graphene and at least one carbonallotrope other than the graphene, and the ratio of the graphene to thecarbon allotrope other than graphene is from 1:100 to 10:1, 1:20 to10:1, or from 1:10 to 10:1. In some embodiments, the additional carbonallotrope is amorphous carbon, carbon black, multi-walled sphericalfullerenes, carbon nanotubes, or graphite. In some embodiments, thegraphene-based carbon material comprises graphene, such as at least 5%graphene, or at least 10% graphene, and may also include multi-walledspherical fullerenes. The graphene-based carbon material is areplacement for conventional carbon black, such that the fillermaterials of the present embodiments contain less carbon black thanconventional elastomer compounds. For example, less than 10% of thefiller material can be carbon black. Embodiments also include methods ofproducing an elastomer compound, where hydrocarbon cracking is performedin a reactor to produce a graphene-based carbon material. In someembodiments, the graphene-based material contains graphene, and/ormulti-walled spherical fullerenes, and/or amorphous carbon. An elastomerraw material (or an elastomer material) is mixed with a filler material,where the graphene-based carbon material is a majority of the fillermaterial for the elastomer compound.

In some embodiments, more than one type of filler material is includedin an elastomer compound. For example, a carbon filler material and anon-carbon filler material (e.g., silica) can be mixed into an elastomercompound. For another example, more than one type of carbon fillermaterial can be used, such as more than one type of the presentgraphene-based carbon materials, and the present graphene-based carbonmaterials mixed with conventional carbon black. In some embodiments, itis advantageous to mix more than one type of filler material to gain thebenefits of each type of filler material. For example, a filler materialthat has a high structure (e.g., as measured by DBP Number) can shortenthe cure time of the compound, and a filler material with a high surfacearea can improve the tear strength of the compound.

In some embodiments, the percentage of graphene of the presentgraphene-based carbon materials can be at least 5%, or at least 10%, orat least 20%, or up to 100% graphene.

In some embodiments, elastomer formulations contain an elastomer and afiller material containing a carbon material. The elastomer formulationscan include a viscosity modifier or a sulfur cross-linker. Additionally,other additives can be included in the elastomer compound. Somenon-limiting examples of other additives that can be added to elastomersare TDAE oil, zinc oxide, stearic acid, antioxidants or antiozonantssuch as 6PPD, a wax material such as Nochek® 4729A wax, TMQ, and sulfur.Additionally, elastomer often include accelerators (e.g., TBBS, alsoknown as N-tert-butyl-2-benzothiazyl sulfonamide orN-tert-butyl-benzothiazole sulfonamide), which promote the formation ofthe elastomeric compound from the constituent components. In someembodiments, all of the additives are mixed into the elastomer compoundsin one stage, or in more than one stage.

In some embodiments, some of the additives can be incorporated with thecarbon materials through either a carbon functionalization approach or anano-mixing approach as described above. There are several advantages ofintegrating additives with the carbon materials, including achievingbetter mixing of the additives with the carbon materials, achieving moredesirable surface activity by incorporating the additive during thecarbon particle formation, and reducing the total number of processsteps required.

In addition to the examples above, there are several other types ofadditives and fillers that can be included in reinforced elastomericcompounds. Some non-limiting examples of fillers that can be included inreinforced elastomer compounds are degradants (e.g., ground calciumcarbonate and ground coal), diluents (e.g., precipitated calciumcarbonate and soft clays), semi-reinforcing fillers (e.g., titaniumdioxide and zinc oxide), and reinforcing fillers (e.g., carbonmaterials, silica, magnesium oxide and thermosetting resins). Somenon-limiting examples of plasticizers that can be included in reinforcedelastomer compounds are petroleum-based plasticizers (e.g., paraffinic,naphthenic or aromatic oils), and non-petroleum-based plasticizers(e.g., glutarates and adipates). Some non-limiting examples of processaids that provide lubrication either at the surface of the elastomer, orin the bulk of the elastomer, that can be included in reinforcedelastomer compounds are fatty acid esters, fatty acid amides,organosilicones and waxes. Some non-limiting examples of antidegradantsthat can be included in reinforced elastomer compounds are antioxidants(e.g., amines and phenols), antiozonants (amines, and quinolines), heatstabilizers, flex agents, light stabilizers, metal ion agents, andnon-gel agents.

Due to the surface area, structure and surface activity of thegraphene-based carbon materials described herein, elastomers containingthese materials can use less accelerator than conventional elastomercompounds, in some embodiments. In other words, compounds containing thegraphene-based carbon materials described herein can use lessaccelerator, or minimize the use of accelerator (e.g., TBBS, or DPG(diphenylguanidine)) and achieve the same cure time as compoundscontaining conventional carbon materials. This is advantageous for anumber of reasons, including the toxicity of the various chemicals usedas accelerators, namely DPG which has stringent regulations surroundingits use. In some embodiments, the concentration of DPG in the compoundscontaining the graphene-base carbon materials described herein(including those compounds containing silica and those without silica)is less than 2 PHR (parts per hundred rubber), or less than 1 PHR, orless than 0.5 PHR, or is about zero.

When elastomers are vulcanized and mixed with reinforcing agents such ascarbon particles, the progression of the vulcanization can becharacterized. One such method for characterizing the progression of thevulcanization is using a rheometer-based measurement (e.g., ASTMD5289-12). The stiffness (and viscosity) of an elastomer increases asthe vulcanization progresses, and the stiffness can be measured in situ(e.g., using a rheometer). Some of the metrics obtained in suchmeasurements are the maximum and minimum torque of the rheometer (i.e.,a measure of the viscosity), the cure time and the scorch time. Themaximum torque is a measure of the stiffness of the cured elastomercompound, and the minimum torque is a measure of the stiffness of theuncured elastomer compound. Several factors can contribute to themaximum and minimum torques, such as the species of elastomer used, thecharacteristics and concentration of any reinforcing fillers, and thetypes and concentrations of accelerants used. In some measurements thetest is completed when the recorded torque reaches either an equilibriumor maximum value. The cure time can then be characterized by a givenchange in the measured torque. For example, the time at which 50% of thecure has taken place (e.g., t₅₀, or tc₅₀) can be determined from thetime when the torque reaches 50% of either an equilibrium or maximumvalue. Similarly, the time at which 90% of the cure has taken place(e.g., t₉₀, or tc₉₀) can be determined from the time when the torquereaches 90% of either an equilibrium or maximum value. The scorch timeis a metric that relates to the time required for vulcanization tobegin, for example the time at which the torque to rise 2 units abovethe minimum torque value (e.g., t_(S)2).

Properties of Elastomers with Graphene-Based Carbon Fillers

The graphene-based carbon materials described herein can be incorporatedinto compounds to produce tires with advantageous properties, includingbut not limited to low rolling resistance (rolling resistance is relatedto fuel economy), high mileage, high winter traction, high ice traction,high wet traction, high fuel economy, high dry handling, high drytraction, high dry handling, high treadlife, and/or high staticdischarge. In some cases, the physical (e.g., surface area, structure,surface activity, particle size) and/or electrical properties (e.g.,electrical conductivity) of the graphene-based carbon materials areresponsible for the improved properties of the compound containing thecarbon materials. For example, the high surface area of thegraphene-based carbon materials is responsible for the high tan deltavalues (at low temperature) of the compounds containing the carbonmaterials, which is predictive of tires with good ice and wet traction.As a second example, the high electrical conductivity of thegraphene-based carbon materials is responsible for the high staticdischarge of the compounds containing the carbon materials (and tiresproduced from the compounds).

Elastomers produced for tire applications typically undergo a suite oftests in order to characterize the ability of the elastomer materials tobe processed, the physical properties of the elastomers, and thepredicted performance in tire applications.

The degree of dispersion of particulate fillers (e.g., carbonreinforcing fillers) in elastomeric compounds can be characterized usingoptical light microscope methods where the image from a sample iscompared to a set of standards. One such measurement is the PhillipsDispersion Rating. In this measurement, a sample is prepared (e.g., bycutting with a razor blade), imaged under specific lighting conditions,and compared to a standard scale. The more visible non-uniformitiesobserved (e.g., macro-scale agglomerates of particles), the worse thedispersion is, and the lower the Phillips Dispersion Rating. ThePhillips Dispersion Rating uses a 10-point scale where a 10 is the leastnumber of non-uniformities observed (i.e., the best dispersion) and arating of 1 corresponds to the most number of non-uniformities observed(i.e., the worst dispersion).

The physical properties of an elastomer compound (e.g., durometerhardness, tensile strength, elongation at break and modulus at differentextensions) can also be measured, for example using ASTM D412-16, andASTM D2240-15. The change in physical properties upon accelerated aging(e.g., heat-aging) can also be measured, for example using ASTM D573-04(2015). Tear strength is another physical property that can be measured,for example, using ASTM D624-00 (2012). The physical properties of anelastomer compound (e.g., durometer hardness, tensile strength,elongation at break, modulus at different extensions and tear strength)can be influenced by many factors, such as the species of elastomerused, and the characteristics and concentration of any reinforcingfillers.

The abrasion resistance of an elastomer is another importantcharacteristic in many applications. The abrasion loss can be measured,for example using DIN 53 516 and ASTM D5963-04 (2015) testing standards.These tests typically include pressing an elastomer sample to thesurface of a rotating drum with an abrasive sheet using a well-definedforce. The abrasion resistance of an elastomer compound can beinfluenced by many factors including the species of elastomer used, andthe characteristics and concentration of any reinforcing fillers.

The compression set of elastomers is a measure of the permanentdeformation remaining after an applied force is removed. The compressionset can be measured, for example using ASTM D395-16e1, Method B testingstandard. These tests typically include the prolonged application of acompressive stress, the removal of the stress, and a measurement of thedeformation of the sample. The compression set characteristics of anelastomer compound can be influenced by many factors including thespecies of elastomer used, and the characteristics and concentration ofany reinforcing fillers.

The dynamic viscoelastic properties of a reinforced elastomer arecommonly used to predict the performance of the elastomer in tireapplications. For example, the dynamic viscoelastic properties can bemeasured using ASTM D5992-96 testing standards. Some common metrics usedare G′ storage modulus, tan delta and J″ loss compliance at differenttemperatures. Each metric relates to a different tire performancecharacteristic. For example, tan delta at higher temperatures such as30° C. and 60° C. are a good predictors of rolling resistance. Highertan delta values indicate higher hysteresis and therefore higher rollingresistance and poorer fuel economy. The G′ storage modulus at lowtemperatures such as −20° C. is a good predictor of winter traction, andthe G′ at higher temperatures such as 30° C. is a good predictor of dryhandling. Compounds with higher stiffness give higher dry handlingbecause the tread compound is stiffer when the tire is cornering througha curve. Dry traction, on the other hand, is quite different from dryhandling. A softer more pliable compound gives better dry tractionbecause it conforms more to the surface of the road and gives morecontact area. Compounds with higher tan delta (higher hysteresis) tendto be better for dry traction. Higher J″ loss compliance at 30° C. isalso a good predictor of higher dry traction. Ice and wet tractionperformance are predicted by higher tan delta (higher hysteresis) atlower temperatures of −10° C. (ice) and 0° C. (wet) because the lowertemperatures are equivalent to high frequencies which are seen withtraction.

Two other dynamic materials properties, which are used to characterizereinforced elastomers are the Mullins Effect and the Payne Effect. TheMullins Effect and the Payne Effect can be measured, for example usingASTM 5992-96 (2011), whereby the modulus versus the dynamic strain of asample is measured in a first sweep, and then repeated in a secondsweep. The Mullins Effect is a measure of the difference between the G′storage modulus at 0.001% strain in the first sweep and the G′ at 0.001%strain in a second sweep. The Mullins Effect is related to the dynamicstress-softening that is observed between the first and second strainsweeps, which can be due to the polymer-filler matrix being pulled apartduring the first strain sweep and not having time to re-form. The PayneEffect is a measure of the difference between the G′ storage modulus at0.001% strain in the first sweep and the G′ at 0.05% strain in a secondsweep. A lower Payne Effect can be indicative of better fillerdispersion because filler particles are finer and more evenlydistributed throughout the polymer with less chance to re-agglomerate.The Payne Effect is typically seen in filled rubber compounds, and notin gum compounds.

The properties of the elastomeric compounds incorporating thegraphene-based carbon materials described herein (e.g., as determinedusing the above tests) can be used as predictors of the performance of avehicle tire manufactured from the compound. For example, a highrheometer maximum torque during mixing combined with a high durometerhardness value and high modulus values predict that the graphene-basedcarbon materials have desirable reinforcement properties, which areadvantageous in tread grade carbon in tires (e.g., the graphene-basedcarbon materials can replace tire filler carbon materials with lowerASTM N classifications, such as N234 and N110). Elastomeric compoundsincorporating the graphene-based carbon materials described herein canalso be produced with high hardness for use in monorail tires, forexample.

In some embodiments, the compound containing the graphene-based carbonmaterials described herein has a median Shore A Durometer Hardness, asmeasured by ASTM D2240-15, from 70 to 80, or from 55 to 80. In someembodiments, the compound containing the graphene-based carbon materialsdescribed herein has a median tensile strength, as measured by ASTMD412-16, from 10 MPa to 30 MPa, or from 15 MPa to 20 MPa, or from 20 MPato 35 MPa. In some embodiments, the compound containing thegraphene-based carbon materials described herein has a median elongationat break, as measured by ASTM D412-16, from 400% to 500%, or from 300%to 400%, or from 200% to 525%. In some embodiments, the compoundcontaining the graphene-based carbon materials described herein has amedian 50% modulus, as measured by ASTM D412-16, from 1.5 MPa to 2.5MPa, or from 1.0 MPa to 2.0 MPa. In some embodiments, the compoundcontaining the graphene-based carbon materials described herein has amedian 100% modulus, as measured by ASTM D412-16, from 2 MPa to 4 MPa,or from 1.75 MPa to 4 MPa. In some embodiments, the compound containingthe graphene-based carbon materials described herein has a median 200%modulus, as measured by ASTM D412-16, from 7 MPa to 9 MPa, or from 5 MPato 9 MPa. In some embodiments, the compound containing thegraphene-based carbon materials described herein has a median 300%modulus, as measured by ASTM D412-16, from 13 MPa to 16 MPa, or from 10MPa to 17 MPa.

The combinations of properties of the compound incorporating thegraphene-based carbon materials can be predictors of the performance ofan automobile tire manufactured from the compound. For example, the highrheometer maximum torque during mixing combined with the high ShoreHardness values and the high modulus values predict that thegraphene-based carbon materials have desirable reinforcement properties,which are advantageous in tread grade carbon in tires (e.g., thegraphene-based carbon materials can replace tire filler carbon materialswith lower ASTM N classifications, such as N234 and N110).

In some embodiments, the compound containing the graphene-based carbonmaterials described herein has a median tear strength, as measured byASTM D624-00 (2012), from 60 kN/m to 70 kN/m, or from 60 kN/m to 110kN/m. The high surface area of the present graphene-based materials canbe responsible for the tear strength of the present compounds beingcomparable to or greater than the tear strength of compounds usingconventional carbon filler. In the cases where functionalizedgraphene-based materials are used, then the functionalization may alsoimprove the tear strength of the present compounds compared to the tearstrength of compounds using conventional carbon filler.

In some embodiments, the compound containing the graphene-based carbonmaterials described herein has a median abrasion loss, as measured byASTM D412-16, from 70 mm³ to 100 mm³ or 80 mm³ to 90 mm³. The structureof the present graphene-based materials (e.g., geometries with highaspect ratios), or the smaller particle size of the presentgraphene-based materials compared to conventional carbon black materialscan be responsible for the abrasion resistance of the present compoundsbeing comparable to or greater than the abrasion resistance of compoundsusing conventional carbon filler.

In some embodiments, the compound containing the graphene-based carbonmaterials described herein has a Phillips Dispersion Rating from 6 to10, or from 8 to 10. The smaller particle size of the presentgraphene-based materials can be responsible for the dispersion of theparticles in the present compounds being comparable to or better thanthe dispersion of conventional carbon filler in elastomer compounds. Inthe cases where functionalized graphene-based materials are used, thenthe functionalization may also improve the dispersion of the particlesin the present compounds compared to the dispersion of conventionalcarbon filler in elastomer compounds.

In some embodiments, the compound containing the graphene-based carbonmaterials described herein has a compression set, as measured by ASTMD395-16e1, Method B from 20% to 30%, or from 25% to 30%. The highsurface area and/or the structure of the present graphene-basedmaterials can be responsible for the compression set of the presentcompounds being comparable to or greater than the tear compression setof compounds using conventional carbon filler. In the cases wherefunctionalized graphene-based materials are used, then thefunctionalization may also improve the compression set of the presentcompounds compared to the compression set of compounds usingconventional carbon filler.

In some embodiments, the compound containing the graphene-based carbonmaterials described herein have electrical resistivity, as measured byASTM ASTM D257-14, from 1×10¹³ Ω-cm to 5×10¹⁴ Ω-cm, or from 5×10¹³ Ω-cmto 5×10¹⁴ Ω-cm, or 1×10¹⁴ Ω-cm to 1×10¹⁵ Ω-cm. The improvements inelectrical resistivity can be attributed directly to the higherelectrical conductivity of the present graphene-based carbon filler.

In some embodiments, the compound containing the graphene-based carbonmaterials described herein have thermal conductivity from 0.1 W/(m*K) to10 W/(m*K), or from 0.1 W/(m*K) to 5 W/(m*K), or from 0.1 W/(m*K) to 1W/(m*K), or from 0.1 W/(m*K) to 0.5 W/(m*K). The improvements in thermalconductivity can be attributed directly to the higher thermalconductivity of the present graphene-based carbon filler.

In some embodiments, the compound containing the graphene-based carbonmaterials described herein has a G′ storage modulus at −20° C., asmeasured by ASTM D5992-96 (2011), from 5 MPa to 12 MPa, or from 8 MPa to9 MPa, or less than 9 MPa. In some embodiments, the compound containingthe graphene-based carbon materials described herein has a tan delta at−10° C., as measured by ASTM D5992-96 (2011), from 0.35 to 0.40, or from0.35 to 1.0, or from 0.8 to 0.9, or greater than 0.8. In someembodiments, the compound containing the graphene-based carbon materialsdescribed herein has a tan delta at 0° C., as measured by ASTM D5992-96(2011), from 0.3 to 0.35, or from 0.3 to 0.6, or from 0.5 to 0.6, orgreater than 0.5. In some embodiments, the compound containing thegraphene-based carbon materials described herein has a tan delta at 30°C., as measured by ASTM D5992-96 (2011), from 0.1 to 0.3, or from 0.15to 0.25, or less than 0.25. In some embodiments, the compound containingthe graphene-based carbon materials described herein has a G′ storagemodulus at 30° C., as measured by ASTM D5992-96 (2011), from 1 MPa to 6MPa, or from 5 MPa to 6 MPa, or from 1.5 MPa to 2.5 MPa, or greater than1.5 MPa. In some embodiments, the compound containing the graphene-basedcarbon materials described herein has a J″ loss compliance at 30° C., asmeasured by ASTM D5992-96 (2011), from 4E-8 1/Pa to 1E-7 1/Pa, or from9E-8 1/Pa to 1E-7 1/Pa, or greater than 9E-8 1/Pa. In some embodiments,the compound containing the graphene-based carbon materials describedherein has a tan delta at 60° C., as measured by ASTM D5992-96 (2011),from 0.1 to 0.3, or from 0.10 to 0.15, or less than 0.15. In someembodiments, the compound containing the graphene-based carbon materialsdescribed herein has a G′ storage modulus at 60° C., as measured by ASTMD5992-96 (2011), from 1 MPa to 4 MPa, or from 3 MPa to 4 MPa, or from 1MPa to 2 MPa, or greater than 1.5 MPa. All the properties described inthis paragraph are believed to be from carbon structure.

In some embodiments, the compound containing the graphene-based carbonmaterials described herein have a Mullins Effect, as measured by ASTM5992-96 (2011), from 1×10⁴ to 1×10⁶, or from 5×10⁴ to 5×10⁵. In someembodiments, the compound containing the graphene-based carbon materialsdescribed herein have a Payne Effect, as measured by ASTM 5992-96(2011), from 1×10⁵ to 1×10⁷, or from 1×10⁵ to 5×10⁶. The ability of thepresent graphene-based materials to dissipate energy (e.g., heat) can beresponsible for the Mullins Effect and/or Payne Effect of the presentcompounds being comparable to or greater than the Mullins Effect and/orPayne Effect of compounds using conventional carbon filler.

The properties of the graphene-based carbon materials and the elastomersdescribed herein indicate that the present graphene-based carbonmaterials can be used as direct replacements for many conventionalcarbon tire fillers. In some embodiments, the present graphene-basedcarbon materials are more reinforcing than many conventional carbon tirefillers, can reduce the need for environmentally hazardous accelerants(e.g., TBBS and DPG), and/or are compatible with silica in elastomericcompounds (e.g., for use in “green tires”).

FIG. 3 is a cross-section of a conventional radial tire structure, withthe circled components indicating areas where the present graphene-basedcarbon integrated materials can be used. Example areas include, but arenot limited to, sidewalls, tread, liner and carcass. Different types ofrubber compounds are typically used in different areas, where the treadrequires higher grade materials (i.e., lower N number, with higherproperties such as abrasion resistance) than the other areas of thetire. Different formulations of the present elastomer compounds can beused for areas such as, but not limited to, the treads, sidewalls andcarcass.

Due to the properties of elastomer compounds containing thegraphene-based carbon materials described herein, these compounds can beused in tires for various industries, such as tires for automotive,aerospace, other aircraft, passenger tires, off-road equipment,earth-mover type vehicles, racing tires, and all other/similarindustrial applications that use tires.

Additionally, the present elastomer compounds with graphene-based carboncan be used in various applications besides tires. For example,fluoroelastomers (FKM) are another possible application of the presentgraphene-based carbon materials, such as for aerospace applications andother extreme high or low temperature environments. Since thegraphene-based carbon has very little, if any, sulfur upon production,it is an attractive substitute for the conventional carbon that is usedfor FKM. Hydrogenated nitrile butadiene rubber (HNBR) is another area ofapplication, where the present graphene-based carbons can be a directreplacement for standard carbon blacks—such as for oil fieldapplications, and other abrasive environments. The present reinforcedelastomer compounds can also be used in applications such as door seals,gaskets, anti-vibration applications, energy dampening applications,hoses, conveyor belts, engine belts, and many others.

EXAMPLES

The present embodiments include compounds comprising an elastomermaterial, a filler material, at least one additive material, and atleast one accelerant material. The filler material comprises agraphene-based carbon material. The graphene-based carbon materialcomprises graphene comprising up to 15 layers, carbon aggregates havinga median size from 1 to 50 microns, a surface area of the carbonaggregates of at least 50 m²/g, when measured via aBrunauer-Emmett-Teller (BET) method with nitrogen as the adsorbate, andno seed particles.

The additive material may be, for example, a material selected from thegroup consisting of: a silane coupling agent, an oil, a zinc oxidematerial, a stearic acid material, a wax material, a plasticizer, anantiozonant, an antioxidant, a viscosity modifier, and a sulfurcross-linker. The accelerant material may comprise, for example,N-tert-butyl-2-benzothiazyl sulfonamide. In other embodiments, theaccelerant material may comprise N-tert-butyl-2-benzothiazyl sulfonamideand diphenylguanidine, where the concentration ofN-tert-butyl-2-benzothiazyl sulfonamide is higher than the concentrationof diphenylguanidine.

In some embodiments, the graphene-based carbon material is a nano-mixedgraphene-based carbon material, where the nano-mixed graphene-basedcarbon material comprises a species selected from the group consistingof silica, zinc oxide, and titanium dioxide. In some embodiments, thegraphene-based carbon material is a functionalized graphene-based carbonmaterial, where the functionalized graphene-based carbon materialcomprises a species selected from the group consisting of H, O, S, N,Si, aromatic hydrocarbons, Sr, F, I, Na, K, Mg, Ca, Cl, Br, Mn, Cr, Zn,B, Ga, Rb and Cs.

The present embodiments also include methods of producing an elastomercompound. FIG. 36 is a flowchart 3600 of an embodiment comprisingproviding a reactor in step 3610 and providing a hydrocarbon process gasinto the reactor at step 3620. Step 3630 involves performing hydrocarboncracking of the hydrocarbon process gas in the reactor to produce agraphene-based carbon material. Step 3640 involves mixing an elastomermaterial with at least one filler material, at least one additivematerial, and at least one accelerant material. The filler materialcomprises the graphene-based carbon material. The graphene-based carbonmaterial comprises graphene comprising up to 15 layers, carbonaggregates having a median size from 1 to 50 microns, a surface area ofthe carbon aggregates of at least 50 m²/g, when measured via aBrunauer-Emmett-Teller (BET) method with nitrogen as the adsorbate, andno seed particles. The reactor may be a thermal reactor or a microwavereactor.

In some embodiments of the methods, the graphene-based carbon materialis a nano-mixed graphene-based carbon material, and the hydrocarboncracking in the reactor further comprises providing a second materialinto the reactor. In different embodiments, the second material providedinto the reactor is selected from the group consisting of: liquids orgases comprising S, liquids or gases comprising Si; H₂ gas, H₂S gas,silane gas, ammonia gas, aromatic hydrocarbon compounds; particles,gases or liquids containing Na, K, B, Cr, Ca, Sr, Mg, Zn, Rb, Cs, Ga,and Mn; particles, gases or liquids containing F, Cl, Br, I, and otherhalogens; and oxygen-containing reactants, oxidizing reactants, ozone,hydrogen peroxide, potassium hydroxide, potassium chloride, hydrochloricacid, nitric acid, chromic acid, permanganates and diazonium salts.

In some embodiments of the methods, the graphene-based carbon materialis a functionalized graphene-based carbon material, and the hydrocarboncracking in the reactor further comprises inserting a hydrocarbonmaterial into the reactor. The methods also include inserting a secondmaterial into the reactor, where the second material is selected fromthe group consisting of: H₂ gas, H₂S gas, silane gas, ammonia gas,aromatic hydrocarbon compounds; particles, gases or liquids containingNa, K, B, Cr, Ca, Sr, Mg, Zn, Ga, and Mn; particles, gases or liquidscontaining F, Cl, Br, I, and other halogens; and oxygen-containingreactants, oxidizing reactants, ozone, hydrogen peroxide, potassiumhydroxide, potassium chloride, hydrochloric acid, nitric acid, chromicacid, permanganates and diazonium salts.

In some embodiments of the above methods, the hydrocarbon crackingprocess and the mixing an elastomer material with at least one fillermaterial, at least one additive material, and at least one accelerantprocess are performed at the same site.

The examples below represent some embodiments of the present disclosure.

Example 1: Elastomer Compounds with Graphene-Based Materials

In this example, graphene-based carbon particles were produced using athermal reactor. Elastomer compounds were also produced using thegraphene-based carbon particles.

The thermal carbon (TC) materials were produced in a thermal reactor, asdescribed herein. In this Example, the TC was a material comprised ofmulti-walled spherical fullerenes (MWSFs) and approximately 30%graphene.

FIG. 4 shows analytical test results for the TC materials, where valuesfor conventional carbon black materials—grades N115, N330, N650, N110,N770 and N339—are also shown for comparison. The “Iodine Adsorption”measurements were performed using ASTM D1510 testing standard, and the“Oil Absorption” (i.e., DBP number) measurements were performed usingASTM 2414, Method B. The TC samples showed iodine adsorption and oilabsorption properties similar to several of the standard materials.Thus, the data indicate that the present graphene-based carbon materialsare a viable replacement for carbon black in rubber formulations. (Note,“BM Carbon” shall be described in reference to Example 2 below.)

FIG. 5 is a graph of oil absorption number versus iodine adsorptionnumber for the TC samples of this Example compared to a range ofconventional carbon black materials. As can be seen, TC is similar toN787, N762, N660. This graph also illustrates additional examples ofcarbon black grades (e.g., N234, N339, N220 and N110) with propertiesthat could be achieved by tailoring the graphene-based carbon such as bycustomizing the graphene-based materials (e.g., by modifying the carbonparticle processing conditions, functionalization, nano-mixing, and/orthe percentage of graphene to other carbon allotropes such as MWSFs).

FIG. 6 describes the formulations of compounds containing an elastomerand carbon material in this Example. The “Control” sample containedIndustry Reference Black No. 8 (IRB #8) filler and the “Tire BlackSample” contained the TC carbon filler of this Example. The elastomer isSBR 1500 and was incorporated at about 100 PHR (parts per hundredrubber). The carbon materials were incorporated at about 50 PHR in bothsamples. Additives were also added, as shown in FIG. 6 (e.g., the zincoxide, sulfur, and stearic acid), and the types of additives andconcentrations were kept constant between the two samples. The TBBS forboth samples were accelerators, which promoted the formation of theelastomeric compound from the constituent components.

FIG. 7 shows physical properties of the “Control” and the “Tire BlackSample” of this Example. The physical properties tested includeelongation, flexural modulus, tensile strength, and durometer hardness,using ASTM D 412-06a and D 2240 testing standards. In these tests, theASTM die C dumbbells were tested at 20 inch/min crosshead speed, thedumbbells rested for 24 hours at 23° C. after curing and before testing,and the durometer values were taken at instantaneous readings. Thetensile strength for a standard passenger tire is 3200-3900 psi. Notethat IRB #8 is a high grade of carbon black material, so although the“Tire Black Sample” embodiment with the present graphene-based carbonmaterial showed lower tensile strength than the control, the tensilestrength of the test sample is in the range of some standard carbonblack materials (e.g., N774 grade).

FIG. 8 shows test results of heat build-up for the “Control” and the“Tire Black Sample” of this Example. A Goodrich flexometer was used, perASTM D623 Method A with a stroke of 175 inches and a speed of 180 cpm.The load for the heat build-up conditions was 143 psi. The “Tire BlackSample” (“Tire Black (1-110G)”) was compared to the “Control” sample.The test results show that the Tire Black (1-110G) built up less heatthan the conventional material, where the temperature rise was 42° F.for the test sample compared to 51° F. for the control. In general, atemperature rise of approximately 50° F. will cause properties of carbonto start to degrade, and reaching an actual temperature of approximately200° F. will cause a tire to blow out. FIG. 8 demonstrates that tiresmade of the present materials result in better dissipation of heat, andconsequently less chance of blowing out the tire.

The DIN abrasion of the “Control” and the “Tire Black Sample” of thisExample was also tested. The testing was done using the DIN 53516testing standard, with 40 rpm conditions and a 10 N load. The abrasionloss for the “Control” sample was 86 mm³ and was 131 mm³ for the “TireBlack Sample.” The specific gravity for the “Control” sample was 1.142and was 1.148 for the “Tire Black Sample.” Note that IRB #8 is a highgrade of carbon black material, so although the “Tire Black Sample”embodiment with the present graphene-based carbon material showed higherabrasion loss than the control, the abrasion loss of the test sample isin the range of some standard carbon black materials (e.g., N774 grade).

Example 2: Elastomer Compounds with Post-Processed Graphene-BasedMaterials

In this example, graphene-based carbon particles were produced using athermal reactor and subsequently post-processed by mechanical grinding.The mechanical grinding was performed using a ball mill, which reducedthe average size of the particles and increased the average particlesurface area. Elastomer compounds were also produced using thepost-processed graphene-based carbon particles.

To quantify the surface area and structure of the ball-milled carbonmaterial, iodine adsorption measurements were performed using ASTM D1510testing standard, and oil absorption (DBP) measurements were performedusing ASTM 2414, Method B. The iodine adsorption number was 110.05 g/kg,and the oil absorption (DBP) was 91.7 cm³/100 g. These results show thatthe surface area and structure were significantly increased over TCmaterials that were not post-processed (e.g., the thermal carbonmeasured in Example 1).

Referring back to FIG. 5, the oil absorption number versus iodineadsorption number for the “BM Carbon” samples of this Example arecompared to a range of conventional carbon black materials. The “BMCarbon” sample contained the post-processed (ball-milled) carbon of thisExample. As can be seen, BM Carbon is similar to N330, N219 and N125.

FIG. 9 describes the formulations of compounds containing an elastomerand carbon material in this Example. The “N339 Carbon Black” sample wasthe control sample and contained conventional carbon black N339. Theelastomer for both samples was a mixture of 70 PHR Buna 4525-0 S-SBR and30 PHR Budene 1207 or 1208 BR. The carbon filler materials wereincorporated at about 55 PHR in both samples. Additives were alsoincorporated into these compounds (e.g., the TDAE oil, zinc oxide,stearic acid, 6PPD, Nochek 4729A wax, TMQ, and sulfur), and the types ofadditives and concentrations were kept constant between the two samples.The TBBS and DPG for both samples were accelerators, which promoted theformation of the elastomeric compound from the constituent components.

FIG. 10 describes some of the key parameters measured during mixing ofthe “N339 Carbon Black” control sample and the “BM Carbon” samplecompounds in this Example, using methods described in ASTM D5289-12. Theequipment and conditions used for these tests were Tech Pro rheoTECHMDR, at a temperature of 160° C. (320° F.) and 0.5° arc. The maximum andminimum torque experience during mixing, the “Cure Time, t₅₀” (time atwhich 50% of the cure has taken place), the “Cure Time, t₉₀” (time atwhich 90% of the cure has taken place), and the “Scorch Time, t_(S)2”(scorch time for viscosity to rise 2 units above the minimum torquevalue) are summarized in FIG. 10. The “BM Carbon” sample had lowermaximum torque, and a slightly longer cure time than the control samplein this Example. Note that N339 grade of carbon black material has asomewhat higher structure than the post-processed carbon material inthis Example (see FIG. 5). The higher structure of the N339 carbon blackcould account for the slightly shorter cure times and scorch times forthe “N339 Carbon Black” control sample compared to the “BM Carbon”sample compounds.

FIG. 11 shows some examples of physical properties for the “N339 CarbonBlack” control sample and the “BM Carbon” sample compounds in thisExample, as produced (i.e., before heat aging). The tests in thisExample were performed using methods described in ASTM D412-16 and ASTMD2240-15. The die C dumbbells in this Example were tested at 20 in/min.The Shore A durometer hardness and tensile strength were higher for the“N339 Carbon Black” control sample compared to the “BM Carbon” sample,indicating that the post-processed carbon in this Example was lessreinforcing than the N339 carbon black. The peak strain (i.e.elongation) and moduli at different strains (i.e., 50%, 100%, 200% and300% strain) were also higher for the “N339 Carbon Black” control samplecompared to the “BM Carbon” sample in this Example.

FIG. 12 shows the same physical properties shown in FIG. 11 for the“N339 Carbon Black” control sample and the “BM Carbon” sample compoundsin this Example, after heat aging for 168 hours at 70° C. in air. The“BM Carbon” material experienced larger magnitude changes in durometerhardness, tensile strength and elongation compared to the controlsample, which indicates that the “BM Carbon” material was less stablethan the control during heat aging.

The tear resistance of the “N339 Carbon Black” control sample and the“BM Carbon” sample compounds in this Example were also measured usingASTM D624-00 (2012) testing standard with a rate of 20 in/min. Threesamples were measured for each. The average tear strength of the three“BM Carbon” samples was 29.67 kN/m (with a standard deviation of 2.60kN/m) compared to an average of 76.96 kN/m (with a standard deviation of2.73 kN/m) for the control samples.

The DIN abrasion of the “N339 Carbon Black” control sample and the “BMCarbon” sample compounds in this Example were also measured using DIN 53516 (Withdrawn 2014) and ASTM D5963-04 (2015) testing standards withcontrol abrasive Grade 184, and 40 rpm and 10 N load conditions. Threesamples were measured for each. The average abrasion loss of the three“BM Carbon” samples was 153 mm³ (with a standard deviation of 4 mm³)compared to an average of 73 mm³ (with a standard deviation of 2 mm³)for the control samples.

The Phillips Dispersion Rating was also determined for the “N339 CarbonBlack” control sample and the “BM Carbon” sample compounds in thisExample. In these measurements, the samples were prepared for the testsby cutting with a razor blade, and pictures were taken at 30×magnification with an Olympus SZ60 Zoom Stereo Microscope interfacedwith a PaxCam ARC digital camera and a Hewlett Packard LaserJet colorprinter. The pictures of the samples were then compared to a Phillipsstandard dispersion-rating chart having standards ranging from 1 (bad)to 10 (excellent). The Phillips Dispersion Rating for the “BM Carbon”sample was 8 compared to a value of 7 for the control samples.

FIG. 13 shows dynamic viscoelastic properties of the “N339 Carbon Black”control sample and the “BM Carbon” sample compounds in this Example,measured using ASTM D5992-96 (2011). These measurements were performedin a temperature range from −20° C. to +70° C., with a strain of 5%, anda frequency of 10 Hz. The control sample was a stiffer/harder compoundthan the “BM Carbon” sample compound in this Example as indicated byhigher G′ elastic modulus values throughout the temperature sweep from−20° C. to +70° C. This measurement also correlates with the higherdurometer level. Because of the higher stiffness level, tire predictorslike snow traction (G′ at −20° C.) and dry handling (G′ at 30° C. and60° C.) are higher for the control sample than for the “BM Carbon”sample. FIGS. 14 and 15 show the same data as FIG. 13, but normalized tothe control sample. The predictors indicate that the “BM Carbon” samplewould be worse for dry, ice and wet traction, dry handling and treadlife, but better for winter traction and fuel economy (rollingresistance) compared to the control compound with conventional N339carbon material.

The physical properties (e.g., tensile strength, modulus, tearresistance, durometer hardness) and the dynamic properties of the “BMCarbon” sample in this Example indicate that the post-processedgraphene-base material in this Example may be used as a filler inrubber, but is not reinforcing enough to be used as a tread grade carbonblack and in its present form. Dynamic viscoelastic testing also showedthat the “BM Carbon” sample compound had low Payne and Mullins effects,which were similar to those of a gum compound.

Example 3: Elastomer Compounds with Graphene-Based Materials

In this Example, graphene-based carbon particles were produced using amicrowave reactor system, as described herein. The particles produced bythe microwave reactor were collected using a gas-solids separationsystem including a cyclone filter follower by a back-pulse filter. Thetemperatures within the cyclone filter and back-pulse filter werecontrolled, which controlled the amount of condensed hydrocarbons on thesurface of the collected particles. Three different graphene-basedcarbon materials were produced using the microwave reactor in thisExample: “LF CYC” were particles collected in the cyclone filter using ahigher temperature (e.g., >300° C.), “LF CYC C6+” were particlescollected in the cyclone filter using a lower temperature (e.g., <300°C.) in order to intentionally condense polycyclic aromatic hydrocarbons(PAHs) on the surface of the particles, and “LF FIL” were particles thatwere collected in the back-pulse filter. The “LF FIL” particles hadsomewhat higher structure and smaller particle size than both the “LFCYC” and “LF CYC C6+” particles. The PAHs condensed on the “LF CYC C6+”particles were intended to alter the surface activity of the particlescompared to the “LF CYC” particles. Elastomer compounds were alsoproduced using the graphene-based carbon particles.

FIG. 16 describes the formulations of compounds containing an elastomerand carbon material in this Example. Sample A was the control sample andcontained conventional carbon black N339. Samples B, C and D containedthe microwave reactor produced carbon of this Example. Sample Bcontained the “LF FIL” particles, sample C contained the “LF CYC”particles, and sample D contained the “LF CYC C6+” particles. Theelastomer for all samples was SBR 1500, and was incorporated at 100 PHR.The carbon filler materials were incorporated at about 50 PHR in allsamples. Additives were also incorporated into these compounds (e.g.,the zinc oxide, sulfur, and stearic acid), and the types of additivesand concentrations were kept constant between the two samples. The TBBSwas the accelerator in all of the samples, which promoted the formationof the elastomeric compound from the constituent components.

FIG. 17 describes the mixing parameters for the compounds in thisExample, and observations from the mixing. Similar mixing procedureswere used for all four compounds in this Example. The mixing speed was60 rpm for all of the compounds. One notable observation was that thegraphene-based carbon materials of this Example (LF FIL, LF CYC, and LFCYC C6+) all dispersed well, but took longer to disperse than the N339carbon black used in control Compound A.

FIG. 18 describes some of the key parameters measured during mixing ofthe compounds in this Example, using methods described in ASTM D5289-12.The equipment and conditions used for these tests were Tech Pro rheoTECHMDR, at a temperature of 160° C. (320° F.) and 0.5° arc. The maximum andminimum torque experience during mixing, the “Cure Time, t₅₀”, the “CureTime, t₉₀”, and the “Scorch Time, t_(S)2” are summarized in FIG. 18. Theexperimental compounds B, C and D, including LF FIL, LF CYC and LF CYCC6+ material respectively, all had higher maximum torque and minimumtorque than the control sample A, but had shorter cure times and scorchtimes than the control sample in this Example.

FIG. 19 shows some examples of physical properties for the controlsample A (“N339”) and experimental sample compounds (B “LF FIL,” C “LFCYC” and D “LF CYC C6+”) in this Example, as produced (i.e., before heataging). The tests in this Example were performed using methods describedin ASTM D412-16 and ASTM D2240-15. The Shore A durometer hardness washigher for all of the experimental samples than for the control sample.The tensile strength was higher for the control sample than theexperimental samples. However, the tensile strength for the experimentalsample B containing the LF FIL materials was only slightly lower thanthat of the control sample. The peak strain (i.e. elongation) was alsosimilar for the control compound A and the experimental compound B.However, the peak strain for the experimental compounds C and D werelower than for the control. The moduli at different strains (i.e., 50%,100%, 200% and 300% strain) were also similar or higher for theexperimental compounds B, C and D compared to the control compound A.

The mixing observations and the physical properties (e.g., tensilestrength, modulus, tear resistance, durometer hardness) of theexperimental compound B containing the “LF FIL” material suggest thatthe “LF FIL” material is reinforcing enough to be used as a tread gradecarbon black replacement in its present form. However, the “LF CYC” and“LF CYC C6+” did not perform as well as the “LF FIL” material. Not to belimited by theory, the higher structure and/or smaller particle size forthe “LF FIL” carbon material compared to the “LF CYC” and “LF CYC C6+”could explain the improved performance of the “LF FIL” compounds in thisExample.

Example 4: Elastomer Compounds with Graphene-Based Materials

In this Example, elastomer compounds were produced using the LF FILgraphene-based carbon particles from Example 3.

FIG. 20 describes several formulations of compounds containing anelastomer and carbon material. The elastomer is SBR 1500 and isincorporated at about 100 PHR (parts per hundred rubber). The carbonfiller incorporated in the “B LF FIL” compound (i.e., the “B compound”)is the graphene-based carbon material from Example 3. The carbon fillerincorporated in the other samples (“A N339”, “E N234”, and “F N110”) aredifferent types of conventional carbon materials in accordance with ASTMstandards. The “A N339” sample (i.e., the “A compound”) contains N339carbon, the “E N234” sample (i.e., the “E compound”) contains N234carbon, and the “F N110” sample (i.e., the “F compound”) contains N110carbon. The carbon materials are all incorporated at about 50 PHR.Additives were also incorporated as shown in FIG. 20 (e.g., zinc oxide,sulfur, and stearic acid), and the types of additives and concentrationswere kept constant between all four samples. The TBBS was theaccelerator in all of the samples, which promoted the formation of theelastomeric compound from the constituent components.

FIG. 21 describes the mixing parameters for the A compound and the Bcompound, and observations from the mixing. The same mixing procedurefor the A compound was also used for the E compound and F compound. Themixing parameters for the B compound were also very similar. The mixingspeed was 60 rpm for all of the compounds. Similar to the compound inExample 3, the LF FIL material dispersed well, but took longer todisperse than the N339 carbon black used in control Compound A.

FIGS. 22 and 23 describe some examples of the key parameters measuredduring mixing, using methods described in ASTM D5289-12. The equipmentand conditions used for these tests were Tech Pro rheoTECH MDR, at atemperature of 160° C. (320° F.) and 0.5° arc. The rheometer data issummarized in FIG. 22, and the torque in N-m versus time during mixingis shown in FIG. 23. The maximum and minimum torques were similar forall of the samples tested, but the cure times and scorch time forCompound B containing the LF FIL material was substantially shorter thanfor the control samples A, E and F. The short Tc90 cure time isindicative of the potential for the LF FIL (and other graphene-basedcarbon materials described herein) to enable the use of less acceleratorin elastomeric compounds containing these carbon materials.

FIG. 24 shows examples of physical properties of the A, B, E, and Fcompounds, measured using ASTM D412-16 and ASTM D2240-15. Compound Bwith the LF FIL material had higher Shore A Durometer hardness than thecompounds containing the conventional N339, N234 and N110 carboncompounds. Compound B with the graphene-based carbon had a slightlylower tensile strength than the conventional N339, N234 and N110 carboncompounds, but it is within the standard deviation of the N234 compound.Compound B with the graphene-based carbon materials had similarelongation to the compounds containing the conventional N339 and N234carbon materials. Compound B with the graphene-based carbon materialshad modulus values similar to the compounds containing the conventionalN339 and N234 carbon materials, and higher modulus values than thecompound containing the conventional N110 carbon compound.

The tear resistance of Compound B containing LF FIL material and thecontrol compounds in this Example were measured using ASTM D624-00(2012) testing standard with a rate of 20 in/min. Three samples weremeasured for each. The average tear strength of the three Compound Bsamples was 65.10 kN/m (with a standard deviation of 0.24 kN/m) comparedto averages of from 74.55 kN/m to 77.00 kN/m (with standard deviationsfrom 0.44 to 1.74 kN/m) for the control samples.

The DIN abrasion of Compound B containing LF FIL material and thecontrol compounds in this Example were measured using DIN 53 516(Withdrawn 2014) and ASTM D5963-04 (2015) testing standards with controlabrasive Grade 191, and 40 rpm and 10 N load conditions. Three sampleswere measured for each. The average abrasion loss of the three CompoundB samples was 87 mm³ (with a standard deviation of 2.6 mm³) compared toaverages from 78 mm³ to 84 mm³ (with standard deviations from 2.5 mm³ to9.9 mm³) for the control samples.

The Phillips Dispersion Rating was also determined for Compound Bcontaining LF FIL material and the control compounds in this Example. Inthese measurements, the samples were prepared for the tests by cuttingwith a razor blade, and pictures were taken at 30× magnification with anOlympus SZ60 Zoom Stereo Microscope interfaced with a PaxCam ARC digitalcamera and a Hewlett Packard LaserJet color printer. The pictures of thesamples were then compared to a Phillips standard dispersion-ratingchart having standards ranging from 1 (bad) to 10 (excellent). ThePhillips Dispersion Rating for the Compound B sample was 9 compared tovalues from 6 to 7 for the control samples. Compound B with thegraphene-based LF FIL carbon materials showed better dispersion than theN339, N234 and N110 compounds containing the conventional carbonmaterials. This was an unexpected result given that the LF FIL materialused in Compound B was in powder form and not pelletized like theconventional carbon materials (N330, N234 and N110) in the compoundsthat Compound B was compared to.

FIG. 25 shows dynamic viscoelastic properties for Compound B containingLF FIL material and the control compounds in this Example, measuredusing ASTM D5992-96 (2011). These measurements were performed in atemperature range from −20° C. to +70° C., with a strain of 5%, and afrequency of 10 Hz.

Compound B with graphene-based carbon materials was a stiffer/hardercompound than the control compounds (A, E and F) as indicated by higherG′ elastic modulus values throughout the temperature sweep from −20° C.to +70° C. This measurement also correlates with the higher durometerhardness for Compound B compared to the control compounds in thisExample. Because of the higher stiffness level, tire predictors likesnow traction (G′ at −20° C.) and dry handling (G′ at 30° C. and 60° C.)are higher than the control compounds with the conventional carbonmaterials. The predictors also indicate that Compound B with the LF FILmaterials would be worse for snow traction but better or comparable fordry handling than the compounds with conventional N339, N234 and N110carbon materials.

Compound B with the LF FIL materials had similar low temperature tandelta values to the compounds with the conventional N234 and N110 carbonmaterials, which would predict similar ice and wet traction. Compound A,with the N339 conventional carbon materials had less hysteresis andlower low temperature tan delta values, which predicts lower traction.

Compound B with the graphene-based carbon materials is a stiffer, hardercompound with lower J″ which means it is predicted to have lower drytraction than the compounds containing the conventional N339, N234 andN110 carbon materials.

Compound B with the LF FIL materials had tan delta values similar to thecompound with the conventional N234 carbon materials, indicating similarpredicted fuel economy. The compound with the conventional N339 carbonmaterial had lower tan delta values and is predicted to have the bestfuel economy. The compound with the conventional N110 carbon materialhad the highest tan delta values and is predicted to have the poorestfuel economy.

FIGS. 26 and 27 show the same data as FIG. 25, but normalized to thecontrol Compound A containing the N339 carbon black material. Comparedto the Compound A, the predictors indicate that the Compound B samplewith LF FIL would be worse for winter traction, dry traction, and treadlife, but comparable or better for ice traction, wet traction, fueleconomy and dry handling.

The following is a comparison between Compound B containing thegraphene-based LF FIL carbon materials and Compound A containing theconventional N234 carbon materials:

a. Compound B had shorter t_(S)2 scorch time along with a shortert_(c)90 cure time. In general, short t_(S)2 scorch times can be an issuewith processing in a rubber factory. However, the t_(S)2 time is ameasurement at the curing temperature, in this case 160° C., which ismuch higher than typical rubber processing temperature (125° C.). Theshort t_(c)90 cure times are advantageous because it is an indicationthat lower concentrations of accelerator could be used.

b. Compound B had similar unaged physical properties (tensile,elongation, modulus, tear) to the compound containing the conventionalN234 carbon materials but it was 4 points higher in Shore Hardness.

c. Compound B did not have significantly different DIN abrasion loss.

d. Compound B had better dispersion.

e. Compound B was higher for Shore Hardness, which is consistent withhigher G′ elastic modulus and stiffness in the dynamic viscoelastictesting. Because of the high stiffness the high G′ at −20° C., tiresmade from the compound containing the graphene-based carbon materialscould have poor snow traction. Similarly, the high stiffness affectedthe dry traction predictor (J″ loss compliance) which indicated thepossibility of poorer dry traction. The rolling resistance, ice and wettraction predictors (tan delta values) of the Compound B were similar tothe compound containing the conventional N234 carbon materials. Finally,the higher stiffness of the compound containing the graphene-basedcarbon materials is an advantage for dry handling and the compoundcontaining the graphene-based carbon materials was predicted to havebetter dry handling than the compound containing the conventional N234carbon materials.

The physical properties (e.g., tensile strength, modulus, tearresistance, durometer hardness) and the dynamic properties of theCompound B indicate that the graphene-based LF FIL materials used inthis Example is reinforcing enough to be used as a tread grade carbonblack replacement in its present form. It should be noted that theformulation components and ratios, as well as the mixing parameters,were not optimized for the graphene-based carbon materials in thisExample. It is therefore likely that the resulting properties, such asthe stiffness and tire performance predictors, of the compoundscontaining the graphene-based carbon materials can be improved, and/ortuned, with optimization of the compound compositions and processingconditions.

Example 5: Elastomer Compounds with Graphene-Based Materials and SilicaReinforcing Fillers

In this Example, elastomer compounds were produced using the LF FILgraphene-based carbon particles from Example 3 and silica reinforcingfillers.

FIG. 28 describes the formulations of three compounds that wereproduced, each containing an elastomer, carbon filler materials, silicafiller materials, and varying amounts of additives and accelerants. Thevalues in the chart in FIG. 28 are all in PHR. For all of the compounds,the elastomers are Buna VSL 4526-2 TDAE Oil extended S-SBR, incorporatedat about 103 PHR, and Budene 1207, S-BR, incorporated at about 25 PHR.The carbon filler incorporated in the “1 N234 TBBS 1.7 DPG 2.0” compound(“Compound 1”) is a conventional N234 carbon material. The carbon fillerincorporated in the other two compounds—“2 LF FIL TBBS 1.7 DPG 2.0”(“Compound 2”) and “6 LF FIL TBBS 2.0 DPG 1.5” (“compound 6”)—is the LFFIL graphene-based carbon material of Example 3, and was produced in amicrowave reactor. The carbon filler materials for all three compoundsshown in FIG. 28 are incorporated at about 15 PHR. All three compoundsalso contain silica filler particles (Ultasil 7000 GR Silica),incorporated at about 65 PHR. Additives were also added as shown in FIG.28 (e.g., Si 69 silane coupling agent, TDAE oil, zinc oxide cureactivator, stearic acid activator, Nochek 4729A Wax, 6PPD Antiozonant,TMQ, Struktol ZB49, and sulfur cross-linker), and were kept constantbetween all four samples. The TBBS and DPG accelerators, however, werevaried between the three samples. The TBBS accelerator was incorporatedat 1.7 PHR for Compounds 1 and 2, and at 2 PHR for Compound 6. The DPGAccelerator is incorporated at 2 PHR for Compounds 1 and 2, and at 1.5PHR for Compound 6. For all three compounds, the additives were added inseveral passes, as shown in FIG. 28, such that after the 1^(st) passsome of the additives were incorporated and the total PHR was about 222PHR, after the 2^(nd) pass a second set of the additives wereincorporated and the total PHR was about 234 PHR, and after the finalpass all of the additives and accelerators were incorporated and thetotal final PHR was about 239 PHR. In this Example, Compound 6 used lessDPG accelerator than Compounds 1 and 2. This was advantageous for anumber of reasons, including the toxicity of DPG, which has stringentregulations surrounding its use.

FIGS. 29 and 30 describe some examples of the key parameters measuredduring mixing, using methods described in ASTM D5289-12. The equipmentand conditions used for these tests were Tech Pro rheoTECH MDR, at atemperature of 160° C. (320° F.) and 0.5° arc. The rheometer data issummarized in FIG. 29, and the torque in N-m versus time during mixingis shown in FIG. 30. The maximum and minimum torques were very similarfor all of the samples tested. The cure times and scorch times were alsovery similar between Compounds 1 and 2, and only slightly longer forCompound 6. The cure time results are noteworthy considering the lowerconcentration of DPG accelerant used in Compound 6.

FIG. 31 shows examples of physical properties of the 1, 2 and 6compounds of this Example, measured using ASTM D412-16 and ASTMD2240-15. The physical properties between the three samples were allsimilar, with the one exception that the tensile strength of Compound 2was slightly better than that of Compound 1 and 6.

FIG. 32 shows the same physical properties shown in FIG. 31 forCompounds 1, 2 and 6 in this Example, after heat aging for 168 hours at70° C. in air. Compounds 2 and 6 showed similar durometer hardnesschanges upon heat aging. The change in tensile strength upon heat agingwas slightly worse for Compound 2 compared to Compounds 1 and 6, but thetensile strength value after heat aging for Compound 2 was very similarto that of Compound 1. The change in elongation at break upon heat agingwas also slightly worse for Compound 2 compared to Compounds 1 and 6,but the elongation at break value after heat aging for Compound 2 wasvery similar to that of Compound 1. The moduli changes upon heat agingwere also similar for each of the three samples in this Example.

The tear resistance of the compounds in this Example were measured usingASTM D624-00 (2012) testing standard with a rate of 20 in/min. Theaverage tear strength of Compound 1 was 53 kN/m (with a standarddeviation of 8 kN/m), which was very similar to the average tearstrength of Compound 2 at 53 kN/m (with a standard deviation of 2 kN/m).Compound 6 had a slightly lower average tear strength at 48 kN/m (with astandard deviation of 4 kN/m).

The compression set for the compounds in this Example were measuredusing ASTM D395-16e1, Method B. The conditions for these tests includedaging button specimens for 72 hours at 70° C., using a deflection of25%, and 0.5 hour recovery time. The average compression set for allthree compounds was very similar, and was from 25.5% to 26.4% (withstandard deviations from 1.1% to 3.5%).

The DIN abrasion of the compounds in this Example were measured usingDIN 53 516 (Withdrawn 2014) and ASTM D5963-04 (2015) testing standardswith control abrasive Grade 177, and 40 rpm and 10 N load conditions.Three samples were measured for each. The average abrasion loss of thethree Compound 1 samples was 83.3 mm³ (with a standard deviation of 6.8mm³). The two experimental compounds had slightly higher abrasion losscompared to the control Compound 1. Compound 2 had an average abrasionloss of 93.7 mm³ (with standard deviation of 8.7 mm³), and Compound 6had an average abrasion loss of 97.7 mm³ (with standard deviation of 0.6mm³).

FIG. 33 shows dynamic viscoelastic properties for the compounds in thisExample, measured using ASTM D5992-96(2011). These measurements wereperformed in a temperature range from −20° C. to +70° C., with a strainof 5%, and a frequency of 10 Hz. FIGS. 34 and 35 show the same data asFIG. 33, but normalized to the control Compound 1 containing the N234carbon black material. Significantly, the two experimental Compounds 2and 6 in this Example had similar or better tire performance predictorscompared to the control Compound 1.

Additionally, the Payne and Mullins Effects were measured for thecompounds in this Example, using a strain sweep at 30° C., with a 10 Hzfrequency in shear mode. The Payne Effect was similar for all threecompounds, and was from 1.44×10⁶ to 1.71×10⁶. The Mullins Effect wasalso similar between Compound 1 (2.49×10⁵) and 2 (2.64×10⁵). The Mullinseffect for Compound 6 was higher (4.48×10⁵). Not to be limited bytheory, the similar Payne Effect for the three samples in this Examplecan indicate that the filler dispersion is similar between the threesamples. Not to be limited by theory, the similar Mullins Effect betweencontrol Compound 1 and experimental Compound 2 in this Example canindicate that the interaction strength between the polymer and thefiller matrix is similar between these two compounds.

The physical properties (e.g., tensile strength, modulus, tearresistance, durometer hardness) and the dynamic properties of theCompounds 2 and 6 indicate that the graphene-based LF FIL materials usedin this Example is reinforcing enough to be used as a tread grade carbonblack replacement in its present form when used in combination with asilica reinforcing filler. It should be noted that the formulationcomponents and ratios, as well as the mixing parameters, were notoptimized for the graphene-based carbon materials in this Example. It istherefore likely that the resulting properties, such as the stiffnessand tire performance predictors, of the compounds containing thegraphene-based carbon materials can be improved, and/or tuned, withoptimization of the compound compositions and processing conditions.

Reference has been made in detail to embodiments of the disclosedinvention, one or more examples of which have been illustrated in theaccompanying figures. Each example has been provided by way ofexplanation of the present technology, not as a limitation of thepresent technology. In fact, while the specification has been describedin detail with respect to specific embodiments of the invention, it willbe appreciated that those skilled in the art, upon attaining anunderstanding of the foregoing, may readily conceive of alterations to,variations of, and equivalents to these embodiments. For instance,features illustrated or described as part of one embodiment may be usedwith another embodiment to yield a still further embodiment. Thus, it isintended that the present subject matter covers all such modificationsand variations within the scope of the appended claims and theirequivalents. These and other modifications and variations to the presentinvention may be practiced by those of ordinary skill in the art,without departing from the scope of the present invention, which is moreparticularly set forth in the appended claims. Furthermore, those ofordinary skill in the art will appreciate that the foregoing descriptionis by way of example only, and is not intended to limit the invention.

What is claimed is:
 1. A compound comprising: a fluoroelastomermaterial; and a filler material including a graphene-based carbonmaterial comprising: a plurality of carbon particles, each carbonparticle comprising graphene including up to 15 layers; and a pluralityof nano-mix additive particles integrated with the plurality of carbonparticles on a particle level, the plurality of nano-mix additiveparticles configured to form one or more aggregates with at least someof the plurality of carbon particles.
 2. The compound of claim 1,wherein the one or more aggregates have a median size betweenapproximately 1 and 50 microns.
 3. The compound of claim 1, wherein thegraphene-based carbon material has an electrical conductivity greaterthan approximately 500 S/m when compressed.
 4. The compound of claim 1,wherein the one or more aggregates have a surface area of at least 50m2/g as measured via a Brunauer-Emmett-Teller (BET) method.
 5. Thecompound of claim 1, wherein the graphene-based carbon material furthercomprises at least one carbon allotrope other than the graphene, and aratio of the graphene to the at least one carbon allotrope is betweenapproximately 1:100 and 10:1.
 6. The compound of claim 5, wherein the atleast one carbon allotrope comprises multi-walled spherical fullerenes.7. The compound of claim 1, wherein the filler material furthercomprises silica, and a ratio of the silica to the graphene-based carbonmaterial is between approximately 10:1 and 1:1.
 8. The compound of claim1, further comprising at least one additive material.
 9. The compound ofclaim 8, wherein the additive material comprises a silane couplingagent, an oil, a zinc oxide material, a stearic acid material, a waxmaterial, a plasticizer, an antiozonant, an antioxidant, a viscositymodifier, a sulfur cross-linker, or any combination thereof.
 10. Thecompound of claim 1, further comprising at least one accelerantmaterial.
 11. The compound of claim 10, wherein the accelerant materialcomprises N-tert-butyl-2-benzothiazyl sulfonamide orN-tert-butyl-2-benzothiazyl sulfonamide and diphenylguanidine, andwherein a concentration of N-tert-butyl-2-benzothiazyl sulfonamide ishigher than a concentration of diphenylguanidine.
 12. The compound ofclaim 1, wherein the graphene-based carbon material is a functionalizedgraphene-based carbon material.
 13. The compound of claim 12, whereinthe functionalized graphene-based carbon material comprises a speciesselected from the group consisting of H, O, S, N, Si, aromatichydrocarbons, Sr, F, I, Na, K, Mg, Ca, Cl, Br, Mn, Cr, Zn, B, Ga, Rb andCs.
 14. The compound of claim 1, wherein a Phillips Dispersion Rating ofthe compound is between approximately 6 and
 10. 15. The compound ofclaim 1, wherein a G′ storage modulus of the compound, measured at atemperature of −20° C., is between approximately 5 MPa and 12 MPa. 16.The compound of claim 1, wherein a tan delta of the compound, measuredat a temperature of −10° C., is between approximately 0.35 and 1.0. 17.The compound of claim 1, wherein a tan delta at 0° C. of the compound,measured at a temperature of 0° C., is between approximately 0.3 and0.6.
 18. The compound of claim 1, wherein a tan delta of the compound,measured at a temperature of −10° C., is between approximately 0.1 and0.3.
 19. The compound of claim 1, wherein a G′ storage modulus of thecompound, measured at a temperature of −10° C., is between approximately1 MPa and 6 MPa.
 20. The compound of claim 1, wherein a J″ losscompliance of the compound, measured at a temperature of −10° C., isbetween approximately 4E-8 1/Pa and 1E-7 1/Pa.
 21. The compound of claim1, wherein a tan delta of the compound, measured at a temperature of 60°C., is between approximately 0.1 and 0.3.
 22. The compound of claim 1,wherein a G′ storage modulus of the compound, measured at a temperatureof 60° C., is between approximately 1 MPa and 4 MPa.
 23. The compound ofclaim 1, wherein the nano-mix additive particles comprise interlayers oforganic and inorganic materials.
 24. The compound of claim 1, whereinthe nano-mix additive particles comprise silica.
 25. The compound ofclaim 1, wherein the nano-mix additive particles comprise silicon. 26.The compound of claim 1, wherein the nano-mix additive particlescomprise ZnO.
 27. The compound of claim 1, wherein the nano-mix additiveparticles comprise metals.
 28. The compound of claim 1, wherein thenano-mix additive particles and the carbon particles have averagediameters less than 100 nm.
 29. The compound of claim 1, wherein: thegraphene-based carbon material is produced using a hydrocarbon crackingprocess; the nano-mix additive particles are introduced during thehydrocarbon cracking process; and the nano-mix additive particles areintegrated with the carbon particles during manufacture of thegraphene-based carbon material.
 30. The compound of claim 1, wherein:the graphene-based carbon material is produced using hydrocarboncracking with a nano-mix additive material; the nano-mix additivematerial is configured to form the particles of the nano-mix additive;and the particles of the nano-mix additive are integrated with thecarbon particles during manufacture of the graphene-based carbonmaterial.
 31. The compound of claim 30, wherein the nano-mix additivematerial is introduced into the hydrocarbon cracking process as a gas, aliquid, or a colloidal dispersion.
 32. The compound of claim 1, whereinthe compound is configured for aerospace applications.
 33. The compoundof claim 1, wherein the plurality of nano-mix additive particles areintegrated with the at least some of the plurality of carbon particlesduring a hydrocarbon cracking process.